## 3 Materials and Methods
### Procedure
#### 3.3.3 Study 3: Usability Testing  
Usability testing [43] is an interface evaluation method where products are tested in controlled laboratory settings involving real users. The users are provided with the predefined tasks to perform on the interface, and their data are recorded through direct observations, videos, audio, or questionnaires. Usability testing aims to find the product's usability and identify the interface problems.  
We performed usability testing on the selected ERP system. In total, 7 participants, 3 male, and 4 females, with computer skills experience with expertise as advanced beginners, took part in the study. Advanced beginners understand causes and fix common errors, though they may not know precisely why the errors occurred and are self-sufficient primarily when performing tasks.  
The users were required to perform the tasks presented in Table 4. The following measures were considered in usability testing studies based on users' tasks during the session.  
1. Task success (0, 0.5, 1).
2. Error number (how many errors made by a user while performing a task).
3. Time spent using Keylogger.
4. User satisfaction (1-5).  
Our expectations for the users were for them to identify quantitative and qualitative problems from their experience. Thus, compile a list of usability problems and recommendations after the test.  
Results  
Table 6 presents the usability problems found by the users in ERP systems. Many usability problems belong to the proposed checklist of usability issues of ERP systems.  
The Keylogger tool is used for logging the users' clicks to obtain the average time needed to complete the task in Table 7. We found the usability problems from the users' perspective in the usability testing. Most of the issues were related to \"missing data and information,\" related to topic 5 (see Table 1). This issue is major as it causes the degradation  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Task** & **Problems** & **Usability Problem under the Topics in Table 1** & **Percentage of Problems in** **This Task** \\ \hline \multirow{4}{*}{Task 1} & Bank report request control is hard to reach. & 3 (**Difficulty in searching and finding desired item/information in interface** and error handling) & \\  & & **In order** & \\ \cline{1-1}  & Labels of user interface controls are unclear. & 3 (**Difficulty in searching and finding desired item/information in interface** and error handling) & \\ \cline{1-1}  & The system does not show a warning before any action. & 1 (**Lack of feedback** and complex interface) & \\ \hline \multirow{4}{*}{Task 2} & Some area of the interface was not visible due to its layout so users cannot find the information. & 5 (**Missing data and information**) & 14.20\% \\ \cline{1-1}  & The information in the dropdown list was unclear. & 5 (**Missing data and information**) & \\ \cline{1-1} \cline{2-5} \multirow{2}{*}{Task 3} & It takes a very long time to select time duration of leave balances for employee. & 1 (Lack of feedback and complex interface) & 28.57\% \\ \cline{1-1}  & & Confirm step buttons was unclear on the interface. & 5 (**Missing data and information**) & 14.20\% \\ \hline \hline \end{tabular}
\end{table}
Table 6: Usability problems found during the usability testing evaluation.  
of the users' performance. It is clear from the Keylogger tool data that users took a longer time to complete the tasks.  
In the next Section, we present the recommendations for designing user interfaces of ERP systems based on our findings and observations from the previous literature and usability evaluation studies.