Designed for Use, 2nd Edition

Let Users Undo Their Actions

Instead of forcing people to deal with constant warnings, undo offers a simple, transparent solution. Unless users accidentally do something unintended, undo is invisible. Once an accident happens, it’s easy to go back.

One crucial note here is that people need to trust your implementation of undo. That means you have to cover as many actions as possible and offer multilevel, “deep” undo, which allows the user to undo more than just the most recent action. If undo doesn’t work reliably or doesn’t go back far enough, people will lose trust in your application. They will hesitate to explore new features, they will be afraid to use features they know, and eventually they will become unhappy with your application altogether. ...