## 2 Theoretical Background and Concept
### Critiques of Technology Acceptance Models  
The technology acceptance models include TAM, TAM2, and UTAUT, each model has its own limitations. For example, TAM has been tested in numerous empirical work such as [18; 33; 34], it was criticized for not providing an adequate information on user's opinion regarding specific technologies and thus, requires further investigations. Another two major limitations were found in TAM related studies, including (i) the explanatory power of TAM (at an average of 40%) and (ii) the mixed relationship results between constructs, with only few studies showing significant relationships, while others were insignificant. For instance, inconsistent findings were reported in the work of [21; 35] regarding the PEOU influence towards attitude, behavioural intention and actual use of technology. Hence, \begin{table}
\begin{tabular}{l l l l l} \hline \hline
**Author(s)** & **Field of Study** & **Respondents** &
\begin{tabular}{l} **Modification of** \\ **Constructs** \\ \end{tabular} & \(\mathbf{R^{2}}\) \\ \hline [PERSON] et al. [24] & Internet banking & Elderly & None & 62.3\% \\ [PERSON] et al. [25] & Mobile banking & Bank Customers & Trust & 65\% \\ [PERSON] et al. [26] & Internet banking & Bank Customers & Perceived risk & 64\% \\ [PERSON] \& [PERSON] [27] & E-learning & University & Trust & 68\% \\  & systems & Students & & \\ [PERSON] \& [PERSON] [28] & Social network & Tourism & Substitute price & \\  & sites & industry & value with privacy & 77\% \\ [PERSON] et al. [29] & Mobile payment & customers in & & & \\  & & Portugal & & \\ [PERSON] et al. [30] & Travel apps & Tourist & - & 58.1\% \\ [PERSON] et al. [31] & Mobile shopping & Consumers in & & \\  & USA and India & added & & 64\% \\ [PERSON] [32] & Smart meters & Consumers in & Perceived Security & \\  & acceptance & Indonesia & and Risk & 63\% \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Applications of UTAUT2 in different sectors. more models were then proposed with extensions, including human and social variables (e.g., TAM2 and UTAUT). Regarding UTAUT, in spite of having high explanatory power as mentioned earlier, a few limitations still exist. For instance, [PERSON] [36] stated that UTAUT has not explored direct effects that could expose new relationships. In another research, it was criticised that the high coefficient of determination value of UTAUT was obtained only when the moderating key variables are present [37]. However, [PERSON] et al. [38] suggested that the proposed moderators in UTAUT should be reconsidered. They clarify the reasons behind not utilizing all the moderators by prior studies as there may not be any variation in the moderator for the adoption and use context. For example, the adoption of a particular technology may have been required by the organization in which all the individuals should use it. In this case, the voluntariness moderator may not be applicable. Another critical element missing from the UTAUT model is the individual behaviour engagement [38]. For instance, the personal characteristics that express the tendency of the individuals may be influential in showing their behaviours. The literature outlines a few personal characteristics involving computer self-efficacy, attitude, and personal innovativeness (e.g., [39; 40]). UTAUT2 on the other hand is different from UTAUT, because it is developed to adapt to the context of customer use, while UTAUT is based on the organizational context. UTAUT2 has been widely accepted and used in other contexts, such as the context of consumer technologies which involve a high cost of implementation in view of the large number of technology devices, applications, and services that targeting consumers [18]. In addition, the constructs which were provided by UTAUT2 are more appropriate for consumer technology acceptance. For example, the theoretical constructs that were found to be significant for consumer decision-making in the use of technology include hedonic motivation, cost (i.e., price), and habit, which were not provided by TAM nor UTAUT.