In a case study of the development of three electronic consumer products, we traced the origins of usability issues. Based on the data collected, an initial, explanatory framework was induced of important drivers of usability in product design. We conclude that - while usability methods mostly focus on gaining knowledge about users and usability issues - in many instances the primary cause of usability problems seems to be a lack of design freedom to implement usability-improving design changes. In addition, the organisational context seemed to influence the design process considerably. Thus, it can be concluded that to conduct user-centred design effectively, the design process should be considered holistically and the organisational context should be taken into account.