One second to lose the user's thought

Brian Goldfarb, my colleague on the ASP.NET team recently attended a web design conference. One of the things that stood out in his report was the following data:

·          Response time limits:

·          0.1 seconds. Limit for having a user feel that the system is reacting instantaneously.

·          1.0 seconds. Limit for user's flow of thought to stay uninterrupted, even though the user will notice the delay.

·          10 seconds. Limit for keeping the user's attention focused on the dialog.  For longer delays, users will want to perform other tasks while waiting for the computer to finish, so they should be given feedback indicating when the computer expects to be done.

Web Designers may want to start paying close attention to this kind of data. Client side applications have long provided instant feedback when the user interacts with any UI element. Broadband access and AJAX now enables web designers to provide a similar experience. After clicking on an image hot spot in a web page, users will no longer have to guess -- "Did I click that or not?"