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
The requirements of economy Economy is the mother of most inventions, not necessity, unless in the sense of poverty and hardship. A requirement for convenience is simply a diluted requirement for ease and economy. It seems to be invariably true that those characteristics which lead people to call a design functional are derived from the requirements of economy and not of use. David Pye, The Nature and Aesthetics of Design Form follows functionEconomy of material and labor function