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
Customers don't know what they want At the end of the presentation someone asked whether he thought they should do some market research to see what customers wanted. "No," he replied, "because customers don't know what they want until we've shown them." Then he pulled out a device that was about the size of a desk diary. "Do you want to see something neat?" When he flipped it open, it turned out to be a mock-up of a computer that could fit in your lap, with a keyboard and a screen hinged together like a notebook. "This is my dream of what we will be making in the mid- to late eighties," he said. They were building a company that would invent the future. Walter Isaacson, Steve Jobs The iMac