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
Do they really need it? Does Google really need playful doodles to deliver the value they consistently provide in search results? Does Stripe really need to spend so much energy on the design of its site and SDK’s, which after all, are primarily for the developers that use their API’s? Does Apple really need to sweat the literally thousands of very subtle and often not consciously noticed interactions on its devices? Marty Cagan, Ensuring Excellence On Taste