## 4 Research Execution and Analysis
### Extraction of Usability Indicators
[PERSON] and [PERSON] (2021) argue that in mobile apps for trading second-hand luxury goods, a user-centric approach should be emphasized, focusing on \"interactive design\" between the platform and users, \"page information architecture\" design, and \"navigation\" design [22]. Based on the indicators from the literature review, a total of 29 usability indicators were compiled after removing duplicates and similar indicators, as shown in Table 4. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Indicator** & **Content** & **Indicator** & **Content** \\ \hline \multirow{2}{*}{Learability} & The ability of users to quickly & \multirow{2}{*}{User-Centricity} & Design and development \\  & learn how to use the app & & & \\  & & & & \\  & & & & \\ \hline \multirow{2}{*}{Property Protection} & Protecting the safety of & \multirow{2}{*}{Convenience} & \multirow{2}{*}{Ease and speed of use during the} \\  & users’ property & & & product or service experience \\ \hline \multirow{2}{*}{Efficiency} & The time required to \multirow{2}{*}{Simplicity in Use} & Simple and \\  & complete tasks & & & \\  & & & & \\ \hline \multirow{2}{*}{Graphic Layout} & The organization and layout of & \multirow{2}{*}{Pleasure} & Satisfaction felt during \\  & visual elements and text & & product use \\ \hline \multirow{2}{*}{Memorability} & The ability of users to remember & \multirow{2}{*}{Immediate Feedback} & The system’s ability to provide \\  & how to operate the app after & & instant responses after \\  & periods of non-use & & user actions \\ \hline \multirow{2}{*}{Interface Simplicity} & A clear interface design without & \multirow{2}{*}{Social} & Encourages interaction between \\  & distracting elements & & users and between users \\  & & & and sellers \\ \hline \multirow{2}{*}{Error Prevention} & Design features that reduce the & \multirow{2}{*}{Consistency} & The degree to which interface \\  & likelihood of user errors & & elements and operational logic \\ \hline \multirow{2}{*}{Findability} & The ease with which users can & \multirow{2}{*}{System Security} & Protects the system from threats \\  & find the information they need & & such as viruses \\ \hline \multirow{2}{*}{Satisfaction} & The overall satisfaction level of & \multirow{2}{*}{Clarity} & The degree to which information \\  & users with the product or service & & is expressed clearly and is easy \\  & & & to understand \\ \hline \multirow{2}{*}{Accessibility} & Ensuring that everyone, including & \multirow{2}{*}{Page Information} & The organization and hierarchical \\  & individuals with disabilities, can & \multirow{2}{*}{Architecture} & structure of page information \\  & use the product without barriers & & \\ \hline \multirow{2}{*}{Flexibility} & The capacity for user & \multirow{2}{*}{Terminology} & Uses vocabulary that users \\  & customization and & & can understand \\  & personalization & & \\ \hline \multirow{2}{*}{Credibility} & Users’ perception of the product’s & \multirow{2}{*}{Navigation} & Helps users quickly find the \\  & or service’s reliability and & & information they need during \\  & trustworthiness & & product use \\ \hline \multirow{2}{*}{Attitude} & The impression or stance users & \multirow{2}{*}{Help} & Provides guidance and solutions \\  & hold toward the product, service, & & for user operations and problems \\  & or brand & & \\ \hline \multirow{2}{*}{Value Realization} & The value obtained from using & \multirow{2}{*}{Error Feedback} & Offers guidance and feedback to \\  & the product & & users when errors are made \\ \hline \multirow{2}{*}{Findability} & The ease with which users can & \multirow{2}{*}{Knowledge and feedback to \\  & find the information they need & & \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Summary of usability metrics for second-hand trading applications.