Website Response Times An Article by Jakob Nielsen www.nngroup.com Users really care about speed in interaction design...A snappy user experience beats a glamorous one, for the simple reason that people engage more with a site when they can move freely and focus on the content instead of on their endless wait. 0.1 seconds gives the feeling of instantaneous response. This level of responsiveness is essential to support the feeling of direct manipulation. 1 second keeps the user's flow of thought seamless. 10 seconds keeps the user's attention. A 10-second delay will often make users leave a site immediately. uxperformanceinteraction
Their wrongness is somehow more immediate In general, a successful design, which Alexander terms a good fit between form and context, can be declared only when we can detect no more [points that conform to the standard against which we judge]. It is "departures from the norm which stand out in our minds, rather than the norm itself. Their wrongness is somehow more immediate than the rightness." Henry Petroski, The Evolution of Useful Things Notes on the Synthesis of Form