Wed, September 11, 2002

Responsiveness vs. Performance

An IBM developerWorks article discusses design and implementation considerations related to Progress Indicators. The article distinguishes between responsiveness and performance. Responsiveness is how quickly an app acknowledges and indicates acceptance of user input. Performance is how quickly it completes a task and displays the final results. A more responsive app contributes more to user satisfaction than quick performance by itself. A quick response can make the application feel faster, even if it takes longer on an overall task.

“Progress indication is needed because: (1) there are inevitable limitations in UI performance, that is, there are always cases where the user will have to wait for a final result, and (2) increased UI responsiveness, or improved communication with the user, can make the wait more acceptable to the user.”

I noticed the other day that the throbber makes Mozilla feel responsive. It activates immediately after clicking a link or entering a URL. The progress indicator in the status bar only seems to show up after a fairly lengthy period of time. For those that want to eliminate the throbber completely, this points out the need for better responsiveness in the rest of the UI.

The article is packed with practical and specific information. All designers and developers would do well to carefully consider the information in this article and how they could improve their application’s responsiveness.

Phoenix for users     To be remembered