=Paper= {{Paper |id=Vol-1293/paper4 |storemode=property |title=Business Process Measurement in Small Enterprises after the Installation of an ERP Software |pdfUrl=https://ceur-ws.org/Vol-1293/paper4.pdf |volume=Vol-1293 |dblpUrl=https://dblp.org/rec/conf/simpda/SiccardiS14 }} ==Business Process Measurement in Small Enterprises after the Installation of an ERP Software== https://ceur-ws.org/Vol-1293/paper4.pdf
      Business Process Measurement in small
    enterprises after the installation of an ERP
                      software.

                     Stefano Siccardi and Claudia Sebastiani

                             CQ Creativiquadrati snc,
                            via Tadino 60, Milano, Italy
                         http://www.creativiquadrati.it




      Abstract. We report the observation of the first six months of operation
      after the installation of an ERP software in a group of small Italian enter-
      prises (some dealers of various products and one manufacturer). Before
      the ERP, no explicit process descriptions existed within the companies:
      the operations were manually performed, using office automation soft-
      ware or legacy programs that were not process oriented. The new ERP
      is equipped with a workflow engine, a number of standard processes that
      should be followed by the users, and a tracking system that logs the main
      steps of the processes. We use process mining tools to analyze the events
      logged by the ERP during the sales, the purchases and the manufacture
      cycles. Our aim is to 1) compare the ideal processes suggested by the
      ERP with the real paths followed by the users 2) describe the eventual
      adaptation of these paths, as the users became acquainted with the ERP
      3) highlight critical segments in terms of time spent, iterations, etc. 4)
      compare the processes of different companies that are in similar business
      areas. The final goal is to get a better understanding of the processes
      and a rationalization of the operations. It must be stressed that both
      the ERP and the main tools used are open source, so that the process
      measurement is affordable even for very small (micro) enterprises.

      Keywords: Business process mining, small enterprises, open source soft-
      ware, enterprise resource planning



1   Introduction

This report deals with the business process measurement in a sample of small en-
terprises in Italy. All the companies in the sample have recently adopted a new
Enterprise Resource Planning (ERP) system, that is Odoo (previously Open-
ERP), available at www.odoo.com.
   The introduction of the ERP was motivated by several reasons, mainly the
necessity of replacing obsolete programs, the aim of integrating the software and
the need to gain better control of operations. One of the main motivations of
the choice of Odoo was its being an open source software.
2       Business Process Measurement in small enterprises

    The process control was not a primary goal at this stage: process design and
measurement are usually activities too expensive, both in terms of time of the
internal resources and of investment in consultancy, to be affordable for micro
enterprises. So they were simply not considered by the entrepreneurs in the set
of the realistic goals. On the other hand, processes in small enterprises are by
no means simpler than in bigger ones, and a correct process understanding and
design can be a major factor of success.
    Another point that we were interested in was the companies’ adaptation to
the new ERP: although we customized the software in order to fit the users’
business habits, it was unavoidable that they had somehow to change their ways
of operating. So, in the first time of operation, we observed that they tried some
different workflows before finding the one that best fit their needs. The changes
in the processes during the first six months of operation, if any, can describe this
adaptation phase.
    As the Odoo system is intrinsically based on workflows, and automatically
records many steps of the business process, it was evident that a very interesting
byproduct of the ERP usage would have been the possibility to represent the
processes as they are actually run. This can offer a number of interesting ideas
to the companies’ management.
    Of course, the process representation would not have been possible without a
process mining tool; we chose PROM rel. 6.4 (available at www.processmining.
org), as it has all the capabilities we needed, and conforms to the open source
philosophy of our projects. The basic ideas upon which PROM has been designed
can be found e.g. in [1]; techniques to compute alignment between models and
event logs are included in the software, and have been used in our analysis (see
e.g. [2]).
    For the preliminary data preparation we used Xesame ([3]).
    The activity of process measurement aims to determine the performance of
business processes, while the process monitoring is the activity to check them
in order to discover some significant aspects (see e.g. [4]). In what follows, we
concentrate on the first, and adopt a six months period of observation. There
are also formal methods to study process adaptation and drift (see e.g. [5], [6]),
however when considering the processes adaptation we limited ourselves to a
qualitative approach.

1.1   The main process
We focused on the process of selling - delivering goods or services - invoicing,
as it is the main one for all the companies of the sample. It is also a process
that can be very complex, as customers can change their mind at several stages
(before and after confirming an order, receiving goods, receiving invoices, etc.).
Moreover it can be stopped and rescheduled several times if the goods to be
delivered are not available, or if they arrive later at the companies’ warehouses.
    Three kinds of documents are involved in the process: a Sale Order (SO),
containing the list of products and services that a customer wants to buy, with
prices and payment terms; one or more delivery orders (OUT), generated by the
                         Business Process Measurement in small enterprises       3

SO, with a list of products that must be taken from the warehouse and sent to
the customer; one or more invoices (INV) that are fiscal documents specifying
amounts to be paid with taxes and that can be created either from the SO or
from the OUT(s).
    When only services are sold no OUT is created, therefore the process is
simpler.
    We also consider the purchase process, consisting of the activity of ordering
goods to suppliers and receiving them. Two documents are created: the Purchase
Order (PO), with the list of products or services to buy; and one or more lists of
items to receive at the warehouse (IN). Finally, for one company of the sample we
also consider the manufacturing process, that is concerned with the Manufacture
Order (MO), the list of products to produce. We limit ourselves to purchases
and manufactures that are triggered by an SO, that is products are bought or
manufactured just when a customer places an order for them.
    The following eventrs have been tracked for the documents described above:
    SOcreate: a sales order is created by a user and is in the draft state. This is
the starting point of the whole process.
    SOmail : a sale order is sent to the customer
    SOconfirm: a sale order is validated and reaches the confirmed status
    OUTcreate: a list of goods to deliver is created in draft status
    OUTconfirm: a list of goods to deliver has been checked and confirmed by
the user
    OUTwaiting: a list of goods to deliver is put in a waiting status, as something
is not available
    OUTready: a list of goods to deliver is ready to be sent
    OUTsent: a list of goods to deliver has been sent to the customer
    OUTinvoice: a list of goods to deliver has been invoiced
    OUTcancel : a list of goods to deliver has been cancelled by the user
    OUTbackord : a list of goods to deliver has been partially delivered and a
back order has been created for the remaining items
    OUTscrap: some items in list of goods to deliver have been marked as
scrapped
    OUTnot2invoice: a list of goods to deliver has been marked not to be invoiced
(e.g. because it replaces something under warranty)
    INVcreate: an invoice has been created in draft status
    INVproforma: an invoice has been transformed in a pro-forma invoice
    INVvalidate: an invoice has been confirmed by the user
    INVcancel : an invoice has been cancelled
    INVpay: an invoice has been paid
    For the purchase process the events are:
    POcreate: a purchase order is created in draft status
    POconfirm: a purchase order has been confirmed by the user
    INcreate: a list of goods to receive is created in draft status
    INreceive: a list of goods has been received
    INcancel : a list of goods to receive has been cancelled
4       Business Process Measurement in small enterprises

    For the manufacturing process the events are:
    MOcreate: a manufacturing order is created in draft status
    MOwaiting: a manufacturing order is waiting raw material
    MOready: a manufacturing order is ready to produce
    MOstart: a manufacturing order production started
    MOdone: a manufacturing order has been produced
    All the above events are defined by the ERP systems, that automatically
keeps track of their changes. The processes involving them have been mined and
are described by the Petri nets in the next sessions.
    The analysis method is the following:
    1 - first we load in PROM the event log extracted by the Odoo database and
preprocessed with Xesame
    2 - we then take note of the main statistics of the complete log
    3 - then we filter the cases in order to obtain cases that can be considered
complete by a business point of view, e.g. cases that have been invoiced and
paid, or, if not, that have been closed in some other reasonable way due to an
agreement with the customer or else that can be analyzed as they have completed
a definite section of the process
    4 - next we build a model in Petri net format of the process as the company
intends it
    5 - at this stage we compare the filtered log to the model and draw consid-
erations about its conformance and the general performance of the system
    6 - we also analyze the filtered log to find users’ behavioural patterns, e.g. if
specific users are concerned with specific actions, or if some users tend to pass
activities to others
    7 - we again filter the log keeping only the cases started in the first month
of operation, then those started in the last two months considered and repeat
steps 5 and 6 on both sets


2     The cases
2.1   The sample companies
Our sample consists of six small Italian enterprises, that were observed during
the first six months of their operations after the ERP implementation. We will
use two digit codes to label them and we will group them according to their
main business models:
    1) Sale of goods that are kept in stock. Sample 01 (professional equipment
and spare parts) and in part sample 06 (electromechanical devices) belong to
this group.
    2) Repair of customers’ devices. Samples 02 and 03 belong to this group, both
in the building industry, even if they sometimes sell devices and spare parts to
their customers.
    3) Sale of goods that are bought on the customer order and of maintenance
services. Samples 04 and 05 belong to this group (electronic devices like PCs and
telecommunication apparatus, software, etc.).
                         Business Process Measurement in small enterprises      5

    4) Manufacture to customer order. Sample 06 produces electromechanical
components to fulfil customer orders, and sometimes to make stock, so in part
belongs to this group and in part to group 1.
    The event logs of sample enterprises are actually small, especially of samples
02 and 03; this is in part due to the fact that we chose the six months test
period and the sample enterprises before knowing exactly how they would use
the software and how many transactions they would process. Probably samples
02 and 03 are so small that it is even questionable if an ERP fits their needs.
    However, as these kinds of enterprises are presently adopting ERP systems
(as open source ERP systems are available), that forces them to follow structured
processes, it is interesting to understand how they face this task.


2.2   General data

All the tracks of all the samples start with the SOcreate event, as expected.
Some general data are summarized in table 1. The first lines refer to the total
log as it is extracted from Odoo.
    The second set of values refers to the log filtered keeping all the cases that
end with INVpay, INVvalidate, OUTinvoice or OUTsent. This means that the
process has been followed at least until some goods have been sent to the cus-
tomer.


                       Table 1. General data of the samples

                            01   02 03 04 05 06
Total Log
Total tracks                 2151 131 35 253 330 2105
Event classes                18 11 11 22 16 26
Events in the shortest track 1    1 2 1 1 1
Events in the longest track 61 20 12 64 50 66
Average events per track     11 9 8 9 9 13
Ending with INVpay           1064 73 11 45 125 845
Ending with INVvalidate      452 38 15 55 -      611
Ending with OUTsent          376 -    - -    -   105
Log of completed cases
Total tracks                 1908 115 27 112 207 1579
Events in the shortest track 4    7 6 5 5 6
Events in the longest track 61 20 12 64 50 66
Average events per track     11 10 10 16 12 15
Min. event classes per track 4    10 6 4 5 6
Max event classes per track 14 11 11 17 15 19
Avg event classes per track 9     10 10 9 9 11
6      Business Process Measurement in small enterprises

2.3   The 01 business sample
The process model is represented by the Petri net in figure 1. Sale orders always
refer to products, even if some services are sold together, so at least one OUT
is expected.
    We note that:
    - the first steps are related to the SO; when it is confirmed, the OUT is
created
    - when the OUT becomes ready, an invoice is created
    - after invoice creation there may be a loop involving invoice cancelling and
creating anew
    - the process of sending goods may be repeated
    - the last steps are validating the invoice and receiving payments
    - no purchase orders are triggered by the sale orders, because the user sells
goods that are kept in stock


                           SO            SO
                           create        confirm




                                         OUT                  OUT
                                         create               waiting




                                                   OUT
                                                   ready




                                         INV
                                         create




                              INV        INV                 INV
                                                             cancel
                              validate   proform



                                                           OUT
                                                           sent
                              INV
                              pay




              Fig. 1. The SO-OUT-INV process model for sample 01.


   Applying the 1903 completed cases log onto this model, we found deviations
mainly related to the events SOconfirm, OUTcreate, OUTwaiting, OUTready,
INVcreate, INVvalidate, INVcancel and, to a lesser extent, INVproforma. The
average throughput time is 1 month. From a time perspective, INVvalidate and
INVcancel are critical; moreover, when a proforma invoice is issued, it is found a
time lag between this event and the actual invoice. Applying only cases ending
with INVpay (1064 items), we have similar results.
                          Business Process Measurement in small enterprises       7

    We then filtered the log for cases starting in the first month of the period,
and found 244 tracks; and for events starting in the last two, and ending with
one of the four events already considered by the end of the period, and found
178 tracks. These filtered logs, once applied onto the model, gave similar results.
The only remarkable difference is the reduction in the average throughput time
from 2 months to about 12 days. This is undoubtedly related to a better ability
in the use of the new system and to the fact that in the first time of operation
the users were still using their old software in parallel.
    The PROM software can highlight actual cases that do not follow the model,
this is useful to discuss with the users if the model has to be modified or if any
unwanted actions are being performed. For instance, 255 cases follow the path:
    SOcreate - SOconfirm - INVcreate - OUTinvoice - OUTsent - INVvalidate -
INVpay
    that is the invoice is created starting from the SO instead of the OUT. This
is an alternative way of operating that can be included in the model.
    On the other hand, 105 cases follow the path:
    SOcreate - SOconfirm - OUTcreate - OUTwaiting - OUTwaiting - OUTready
- INVcreate - OUTwaiting - OUTready - OUTsent - INVvalidate - INVpay
    probably meaning that sale orders are modified later than expected, when
an OUT has already been created. There are also much more complex exam-
ples, involving multiple sequences of OUTcreate - OUTconfirm - OUTcancel -
OUTnot2invoice - OUTcreate etc.
    This, in turn, can suggest the opportunity of clearer communication with the
customers, so that they can place their orders correctly at the first time.
    Finally, selective filtering of the log shows that all the users are involved in
all the events, that is there is no user dedicated to a specific process section.


2.4   The 02 and 03 business samples

As 03 is a spin off of 02, these two samples are quite similar. Both the companies
are very small and almost all the transactions were recorded by a single user, so
a general uniformity of behaviour is found in the data.
    The process model for both 02 and 03 is represented by the Petri net in figure
2. Sale orders refer always to products, even if some services are sold together,
so at least one OUT is expected.
    We note that in contrast with the 01 process, no loops are considered in this
model.
    Applying the log of completed cases of sample 02 (115 cases) and of sample
03 (27 cases) onto this model, we found deviations mainly related to the event
INVcreate only. The average throughput time is 2.3 months for sample 02 and
1.35 for sample 03. From a time perspective, the main critical event for both
samples is INVpay; this probably reflects a commercial issue and is not related to
the process complexity. For sample 03 also OUTready is critical, whose average
throughput time is 20 days; this probably reflects the fact that the company
business mainly consists of fixing customers’ devices, so when something arrives
8       Business Process Measurement in small enterprises

                   SO       SO
                   create   confirm




                                      OUT      OUT       OUT     OUT
                                      create   confirm   ready   sent




                                                                 OUT
                                                                 invoice




                                                                 INV
                                                                 create



                                                                 INV
                                                                 validate




                                                                 INV
                                                                 pay




          Fig. 2. The SO-OUT-INV process model for samples 02 and 03.


at their warehouse, time is needed to repair it before it can be sent back to the
customer.
    The filtered logs of sample 02 for cases starting in the first month and in the
last two months, once applied onto the model, gave similar results.
    As the cases are very few for sample 03 we did not compare the first months
to the last ones.
    Although the model is quite linear, the analysis of tracks highlighted some
cases comprising loops and some degrees of complexity. Their number, however,
was so low that they can be considered exceptional cases more than an indication
of a more complex process. An example with multiple OUT and INV processing
is shown in figure 3. Here an OUT can be cancelled after being confirmed and
declared ready, and even when the invoicing process has started, by a manual
action that has been represented as an ”invisible” task (see e.g. [7]), so that
it must be created again. Multiple invoices are created, one just after the SO
confirmation, and others after sending goods.


2.5   The 04 and 05 business samples

In both samples, sales are of two different kinds: sometimes the user sells devices
and equipment, that originate physical movement of goods (OUTs) and purchase
orders; other times they sell services, e.g. assistance contracts, that do not imply
any OUT. Moreover they manage assistance agreements with their customers,
that have a single sale order and several invoices to be paid e.g. quarterly, so it
                                        Business Process Measurement in small enterprises   9



        SO
        create




        SO
        confirm
                              OUT
                              confirm
                                              OUT
                                              ready
                  OUT
                  confirm




        INV
        create




        OUT
        invoice




 OUT
 sent
                                             INV
                                             pay




                            INV
                            validate




                                   Fig. 3. A complex case of sample 02.



can happen that payment is not found as the last event in many recorded cases.
The users usually buy products when a SO is received, so the PO process is
triggered.
    For both samples two business process models are found: for sample 04, 124
cases involve some physical products and 129 services only, for sample 05, 177
cases involve some physical products and 153 services only.
    For 04 the filtered log of complete cases contains 58 cases involving products
and 54 service cases.
    For 05 the filtered log of complete cases contains 92 cases involving products
and 115 service cases. Moreover 91 cases end with the SOmail event, that is they
are quotations that the customers did not accept.
    The first process is represented by the Petri net in figure 4 and the second
in figure 5.
    We note that for the first process:
    - the first steps are related to the SO; when it is confirmed a PO is created
    - when the PO is confirmed, an IN is created waiting for the purchased
products; when products are received the OUT becomes ready
    - after sending the OUT the invoice is created, validated and paid
    - there can be change requests before invoice validation, that restart the
process modifying the OUT
    For the second process:
    - the first steps are related to the SO; when it is confirmed an INV is created
10            Business Process Measurement in small enterprises

   - after invoice creation there is a loop involving invoice cancelling and creating
anew, or receiving a payment and creating a new invoice


     SO        SO        OUT
     create    confirm   create




                                  OUT
                                  waiting

                                            PO
                                            create

                                                                        IN
                                                                        received

                                                     PO        IN                  OUT
                                                     confirm   create              ready




                                                                                                  INV
                                                                                                  cancel




                                                                                           OUT    INV
                                                                                           sent   create   INV
                                                                                                           validate




                                                                                                           INV
                                                                                                           pay




     Fig. 4. The SO-PO-OUT-INV process model for products of samples 04 and 05.


    Applying the cases log onto these models, we did not find significant devia-
tions. For the product process of sample 04 the average throughput time is 1.4
months and for sample 05 it is 1.8 months. From a time perspective, no specific
events are critical.
    For the service process of sample 04 the average throughput time is 2.7
months. From a time perspective, INVcreate is critical; however, as these kind
of sales involve long periods this could be a characteristic of the business (an
invoice being issued quarterly in most cases).
    For the service process of sample 05 the average throughput time is 1.7
months. From a time perspective, no specific events are critical. The logs are in
good agreement with the model.
    As the cases of sample 04 are very few, we did not compare the first month
to the last ones.
    For sample 05 comparing cases of first month to the last two, we found that
in the first month the average throughput time was higher (2.45 months instead
of 11 days for products and 2.5 months instead of 10 days for services).
    Finally, selective filtering of the log shows that in sample 04 all the users
are involved in all the events, moreover a single user was involved in about two
thirds of the cases.
                          Business Process Measurement in small enterprises      11


      SO         SO           SO
      create     mail         confirm




                                        INV
                                        create




                                                 INV
                                                 validate   INV
                                                            pay



                                                            INV
                                                            cancel




        Fig. 5. The SO-INV process model for services of samples 04 and 05.


   In sample 05 all the users are involved in the SO and OUT processing, but
only 3 in invoicing and 2 in purchasing.


2.6   The 06 business sample

The user manufactures products both for keeping stock and to fulfil specific sale
orders, so the MO process is triggered by an SO for some products. Most sales
involve products, although 179 service SO have been found.
    The filtered log of complete cases contains 441 cases involving products specif-
ically manufactured for the SO and 1138 cases involving products taken from
the warehouse.
    The first process is represented by the Petri net in figure 6, while the second
is similar to the one already analyzed in figure 1.
    We note that for the first process:
    - the first steps are related to the SO; when it is confirmed a MO is created
    - when the MO is done, the OUT becomes ready
    - after sending the OUT the invoice follows its usual process
    Applying the cases log onto these models, we did not find significant devia-
tions. For the first process the average throughput time is 3.1 months. This long
time is probably due to customers placing their orders even months in advance.
From a time perspective, the only event that needs further analysis is the MOre-
ady as it is sometimes delayed for lack of raw materials, or sometimes due to an
agreement with the customer about the delivery date. The main deviations from
12     Business Process Measurement in small enterprises

           SO       SO
           create   confirm




                     OUT        OUT
                     create     waiting




                              MO          MO        MO              MO                 MO
                              create      waiting   ready           start              done




                                                            OUT             OUT               OUT
                                                            ready           sent              invoice




                                                                                                         INV
                                                                                                         pay

                                                                              INV             INV
                                                                              create          validate

                                                                                                         INV
                                                                                                         cancel




            Fig. 6. The SO-MO-OUT-INV process model for sample 06.


the model are cases where products are delivered in two or more shipments, and
backorders are created.
    For the second process the average throughput time is 2.5 months. From
a time perspective, no specific events are critical. Some deviations from the
model are found for the events SOconfirm and OUTconfirm, probably due to
late changes to the SO requested by the customers.
    Comparing the first month of operation with the last two, we found that
the main difference is a decrease in throughput time and in case length, that
probably means that the users gradually become acquainted with the system
and do not need to cancel and redo operations if not in exceptional cases.
    Finally, selective filtering of the log shows that although 9 users recorded
some transactions, sales orders and invoices were usually managed by 3 users,
manufacturing by 2 others and delivering by all of them.


3    Discussion

The results of our analysis show that, in general, the processes follow the models
that the users have in mind for their ”normal” business cases. This is somewhat
in contrast with the subjective impression that the users themselves have of their
own business.
     In the preliminary meetings that we had, to check if the ERP would actually
fit the companys’ needs, the users described many complex situations that could
                          Business Process Measurement in small enterprises      13

arise, as if they were very common. Looking at the data, it turned out that
these are actually exceptions; it is true that they can be very involved, and can
generate time loss and dissatisfaction, but they are rarer than expected.
     Although the data are too few to get exact statistics, the indication is that
criticality is related to exceptional cases and not to the average ones.
     We discussed specific cases, like that of fig. 3, with the users, and found
that the main source of complexity, for all samples, consists of the customers’
requests to change their agreements at a late stage. That is, some customers
want to change their SO after confirming them, or even after they have received
the products; or they want to change the shipment or payment conditions, etc.
This means that documents must be cancelled and processed again, often with
consequences on other documents.
     It is interesting that we found two different reactions to the above remarks.
Some managers told us that their goal is to be flexible, and that to fulfill their
customers requests is exactly their mission. They think that complexity is in-
herent to their job, and used the cases logs to ask new implementations to our
ERP to fit the way they run their business.
     Other managers, on the contrary, realized that simpler processes are more
efficient, and decided to follow the ERP standard processes for as long as possible.
They defined some new internal rules for this, e.g. a standard time to wait
before confirming the main documents (e.g. SO). If a customer wants to change
something after, he will have to pay an extra fee for the reprocessing of the order.


4   Conclusions

We applied process mining techniques to a sample of micro enterprises, that
would not be able to consider their own processes in other ways. The main
goal of this activity is, in our opinion, to bring process design to the managers’
attention.
    About our business sample, we observe that:
    - processes of similar business are very similar, for instance those of sample
04 and 05, and in part also of sample 01 and 06
    - in general the actual processes follow the models, and specific deviations
can be discussed with the managers to suggest new ideas; anyway they are more
often exceptional cases than variants of the models
    - we did not observe process modification or adaptation in time; the main
difference between the first and last months is an increase in performance. As it
is not realistic that the business itself has quickened so much in six months, this
is probably due to an increase in the users’ familiarity with the system
    - especially in the smaller samples, there are no fixed correlations between
tasks and people (everybody does everything), while bigger companies tend to
assign specific roles to the users
    Finally, we note that in this analysis we used the standard events traced by
Odoo, but it is possible to trace any events that the users think could be relevant
for their business.
14      Business Process Measurement in small enterprises

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