The MUSiC performance measurement method

"Building usability into a system requires more than knowledge of what is good. It requires more than an empirical method for discovering problems and solutions. It requires more than support from upper management and an openness on the part of developers. It even requires more than money and time. Building usability into a product requires an explicit engineering process. That engineering process is not logically different than any other engineering process. It involves empirical definition, specification of levels to be achieved, appropriate methods, early delivery of a functional system, and the willingness to change that system. Together these principles convert usability from a 'last minute add on' to an integral part of product development. Only when usability engineering is as much part of software development as scheduling can we expect to regularly produce products in which usability is more than an advertising claim."