Countless times i've been victim of the "do you want to save?" dialog where the replies were |Yes|No|Cancel|. In some cases the brain knows it made a mistake, and whatever dialog comes, the reply should be the negative one. And with those options, the subconscious clicked No (the most destructive operation) before I knew what was happening. To me, the buttons should read |Save|Discard|Go back| in whatever order the creator wants. I think that even the dialog could just skip the text, with those button labels it isn't needed at all.