From task-oriented to goal-oriented Web requirements analysis

Task analysis has been used traditionally in HCI and CSCW to define requirements for user interfaces, Web-based or otherwise. This paper argues that a shift of paradigm is needed in Web engineering from task-oriented to goal-oriented approaches for designing applications delivering a quality user experience and achieving the objectives of the stakeholders. Task models focus on fine-grained and precisely defined user needs, thereby risking a commitment to premature design decisions. Moreover, since task analysis focuses on users doing things with the system, tasks do not capture the goals of other stakeholders who are not users. Goal-oriented methods, on the other hand, provide specific support for coping with high-level users' and stakeholders' goals, facilitates the exploration of design alternatives and the definition of requirements at a suitable level of abstraction. As such, goal-based techniques are more suitable for early stages of requirements analysis; task models can be used for later stages, such as detailed interaction design and usability evaluation. The paper conducts a detailed comparison of task and goal-analysis design techniques, using an ongoing project for a museum Web site to illustrate the two techniques and their relative strengths.