Iterative User Interface Design

by Jakob Nielsen on November 1, 1993

Summary: Redesigning user interfaces on the basis of user testing can substantially improve usability. In four case studies, the median improvement in overall usability was 165% from the first to the last iteration, and the median improvement per iteration was 38%. Iterating through at least three versions of the interface is recommended, since some usability metrics may decrease in some versions if a redesign has focused on improving other parameters.