(From Communications of the ACM (CACM), 1989)
Designers striving for user interface consistency can resemble Supreme Court justices trying to define pornography: each of us feels we know it when we see it, but people often disagree and a precise definition remains elusive. A close examination suggests that consistency is an unreliable guide and that designers would often do better to focus on users’ work environments.

The Case Against User Interface Consistency (PDF, 1.3 mb)