Utilising Perspectives to Improve Completeness in Industrial Requirements Specifications

In projects with requirements-related troubles the reason is often plainly that too little effort has been spent on requirements engineering (RE). Our varied industrial experience repeatedly showed, however, that even in projects with plenty of RE-budget and -efforts spent numerous problems are often found during acceptance testing that can still be traced back to incomplete or even missing requirements. How is that possible? After observing this repeatedly throughout more than eight years of industrial experience we performed a careful, in-depth qualitative analysis on the underlying root causes that lead us to the hypothesis we present in this paper: requirements engineers often tacitly lay a strong focus on one particular perspective in text-based requirements documentation, while the others typically remain un- or underspecified. Thus, incompleteness arises. In this paper we summarise our observations and present a solution idea that more explicitly considers the different perspectives during the RE process. This can significantly increase requirements completeness, lead to an improved overall balancing of RE efforts and, hence, also lead to higher chances for project success.