Does Quality of Requirements Specifications Matter? Combined Results of Two Empirical Studies

[Background] Requirements Engineering is crucial for project success, and to this end, many measures for quality assurance of the software requirements specification (SRS) have been proposed. [Goal] However, we still need an empirical understanding on the extent to which SRS are created and used in practice, as well as the degree to which the quality of an SRS matters to subsequent development activities. [Method] We studied the relevance of SRS by relying on survey research and explored the impact of quality defects in SRS by relying on a controlled experiment. [Results] Our results suggest that the relevance of SRS quality depends both on particular project characteristics and what is considered as a quality defect; for instance, the domain of safety critical systems seems to motivate for an intense usage of SRS as a means for communication whereas defects hampering the pragmatic quality do not seem to be relevant as initially thought. [Conclusion] Efficient and effective quality assurance measures must be specific for carefully characterized contexts and carefully select defect classes.