## 5 Results: Assisted Service Composition
### Assisted-Composition Problems and Overall Perception
A plausible explanation might be the easy nature of the assisted-composition approach and the level of assistance provided to users by the tool, without considering the limitations and lack of freedom imposed on the expert sample by the assisted-composition approach. **Conceptual problem one:** Basic capabilities of the assisted-composition design approach. E.g., \"I do not find the selection process intuitive; it should be a flow of processes, perhaps page by page,\" P5, non-programmer. \"A little difficult as some services were compatible and some not without explanation. Would like reasoning behind decisions,\" P1, non-programmer. \"I would prefer to see and input logic and see how things work rather than click and drag. The process is too simple and there is no opportunity to see why things are happening,\" P11, programmer. The non-programmers were intimidated by the terminology and language used within the tool, as they were deemed technical and complex. However, this did not emerge as an issue for the expert sample. **Conceptual problem two:** Terminology and technical jargon. E.g., \"The language is too complicated; for example, press execute to deploy composition,\" P11, non-programmer. \"How to use guide is a little technical and complicated,\" P6, non-programmer. Both groups of users were undecided about differences between the candidate services under each activity of the design template, making the selection of services a challenging task. The tool did not provide any systematic criteria to demonstrate the quality of services. **Conceptual problem three:** Differentiation between the services. E.g., \"I do not understand the difference between services. In terms of service provider it is a little unclear,\" P5, non-programmer. \"Again, I have two services. I don't know which one to go for,\" P8, programmer. \"What is this is BACS service, and what is the difference between these services,\" P4, programmer. Finally, the non-programmers complained about the inability to view the outcome of their composition efforts and test the composite application. This observation is aligned with the findings of [PERSON] et al. [11], where end-users emphasized the need to view runtime results as the development process unfolds. Non-programmers P1 and P9 suggested that availability of \begin{table}
\begin{tabular}{c c c} \hline \hline
**Conceptual problem** & **Non-Programmers** & **Programmers** \\ \hline Basic capabilities of composition process and implicit & 38\% & 64\% \\ application logic & & \\ \hline Terminology and technical jargon & 23\% & 9\% \\ \hline Differentiation between services & 15\% & 18\% \\ \hline Absence of runtime effects & 15\% & 0\% \\ \hline Other disperse problems & 9\% & 9\% \\ \hline \hline \end{tabular}
\end{table} 
Table 11: Conceptual problems during assisted composition. runtime effects aids understanding and allows users to inspect the behaviour of the application and debug any unapparent problems. **Conceptual problem four**: Absence of runtime effects. E.g., \"I cannot see the results. If this was real, I would just go online and find out and use it,\" P1,  
non-programmer. \"It was easy, but I wish I could see the end result, so I could understand what I have done,\" P9,  
non-programmer. In respect to usability problems, non-programmers had difficulty manipulating the \"Police Registration\" activity, as it could only be removed using a context menu, which was not obvious (23% of themes). They were also unsure as to why some services were greyed out upon selecting a specific service (17% of themes). However, this confusion diminished as soon as the experimenter explained that the greying-out feature highlights incompatibility of services. Other comments focused on general issues with the user interface. Despite the above challenges, the non-programmers praised the tool as being easy to follow; e.g., \"It is easy to follow the logical steps,\" P4, non-programmer.