User Interface 7 East Conference - Personas: Matching a Design to the Users' Goal We hear all the time from designers that they're faced with the huge challenge of designing products and web sites for a large number of different users. Many designers tackle this problem by making the functionality of the web site or product as extensive as possible. To do this, they outline all of the goals of each user, identify any commonalities between these goals, and add all of the functionality needed to satisfy these common goals.

This one-size-fits-all approach worked for designers back in the days when the functionality of software and web sites was simple, with users confined to a very limited set of goals. But today's web sites and software are vastly more complex and present designers with the unwieldy problem of trying to include functionality for thousands of users all with very different goals. In theory, by increasing the product functionality to account for many users' goals, designers are satisfying a larger audience base. We've observed, however, that by trying to satisfy the needs of *all* users, designers often fail to satisfy the needs of *any* one user.
http://www.uiconf.com/uie-7/goodwin_article.htm