Generally, adding "undo" of some kind doesn't seem like a great idea. Too much complexity to solve a simple problem which virtually never arises in my experienc

Generally, adding "undo" of some kind doesn't seem like a great idea. Too much complexity to solve a simple problem which virtually never arises in my experience. I've always found the "«save» «discard changes» «cancel»" dialog to be effective. The outer (easy) "save/cancel" choices are non-destructive. The save dialog is a file selector which can be easily canceled and "cancel" brings you right back into the program which you are free to try quitting again. And face it, when we form habits like this (which, I agree, are natural and to be accepted) we tend not to form them around the longer options. I always scan the "discard..." button semi-consciously before clicking it because the information is long, and specific to the operation (i.e. throwing everything away) so if you do manage to form a habit around "discard changes" it will apply only when that is what you want to do. (You probably won't form a habit about generally clicking the largest button regardless of the situation.) A solution I do not like is using "clever" dialog window placement or mixing up button orderings. These are just frustrating and do little to solve the problem.