"Are You Sure" versus "Undo"

From Aza Raskin at A List Apart comes a very insightful look at user interface element which is very common, but very commonly poorly designed: “Are You Sure?” dialog boxes in software. Take the example of deleting a file. When we humans get used to routines and then blaze through the things we’re familiar with – so when we delete that file and the dialog box comes up saying “are you sure?”, we know to expect it, we don’t really think about it, and we click “OK.” Only then does the realization hit us that, oh damn, I didn’t want to delete that file! But I already clicked OK! It’s done, it’s gone, nooooo! Ahem, dramatics aside, everyone’s probably experienced this kind of thing. What’s needed instead is an “undo” function – something that never bugs us in everyday usage, but is there the few times that we actually need it. Besides being more effective, this method is more efficient – the user isn’t bugged with dialog boxes and extra clicks that become a useless routine. It’s really a win-win in interface design, and yet it hasn’t even been universally adopted in a company known for excellent interface – as Raskin points out, Google’s Gmail makes wonderful use of “undo,” but Google Calendar still hits you with “are you sure?” every time. This is one of those little things that makes a real difference in usability – if only it can find its way into the stuff we use!
[via the product usability weblog]