Assessing and Evaluating Functional Suitability of Software

While formal task models allow definition and time-based assessment of user-interaction, they have not yet been used as a baseline for assessing the variability patterns of user interaction with software. Consequently, operationalizing these variability patterns enables us to evaluate how suitable the defined task-execution paths are for the user to achieve a predefined goal. Improvements of the software could thereby be evidence-based on knowledge of changes’ effects on functional suitability for the user rather than on prospective or opinion-based usage scenarios. Following a design thinking approach tailored to software engineering, understanding and observing these variability patterns are mandatory steps for continuous user-centered improvement of software. In practice however, due to the absence of an operational quality model for functional suitability it is hardly possible to effectively put these operational measures into context and to derive concrete software improvement actions. Having operational suitability metrics is even more important for software engineers as it allows to increasingly focus development activities especially on functionality which has business value for the user.