For products to be successful in the 1990s, they will need to simultaneously meet consumer/user needs along three perspectives: usefulness, usability, and desirability. A useful product is one that people need and will use. A usable product is one they can use or learn to use. A desirable product is one they want. The only way to ensure the development of products that are useful, usable and desirable is to incorporate user-centered research throughout the entire product development process.
