Chapter 33: Eliminating Errors

In Chapter 30, we discussed the bulletin dialog, issued unilaterally by a program when it is has a problem or confronts a decision that it doesn't feel capable of answering on its own. In other words, bulletin dialog boxes are used for error messages, notifiers, and confirmations, three of the most abused components of modern GUI design. With proper design, these dialogs can all but be eliminated. In this chapter, we'll explore how and why.

Errors Are Abused

There is probably no more abused idiom in the GUI world than the error dialog. The proposal that a program doesn't have the right—even the duty—to reject the user's input is so heretical that many practitioners dismiss it summarily. Yet, if we examine this assertion rationally and from the user's—rather than the programmer's—point of view, it is not only possible, but quite reasonable.

Users never want error messages. Users want to avoid the consequences of making errors, which is very different from saying that they want error messages. It's like saying that people want to abstain from skiing when what they really want to do is avoid breaking their legs. Usability guru Donald Norman (1989) points out that users frequently blame themselves for errors in product design. Just because you aren't getting complaints from your users doesn't mean that they are happy getting error messages.