Press CTRL + Z to Undo

Don't we all just love the undo command? Every time I did something wrong, I just simply press ctrl-z and waa laa, I just undid the parts I wish to delete. But there are times when I was just so immersed in finishing my work only to realize that I've made a mistake somewhere along the way and finding myself pressing the keyboard like a mad man to find out where did I make the mistake. And by the way, did you know the amount of times you can undo on one application is actually based on how much memory that program is used to store the working history? Some let you undo 50 times, some let you undo 5 times, some doesn't even undo. And when you chances of undoing ended before you managed to recover those many wrongs, wouldn't you just close the application and start from scratch again? Or perhaps just leave it because you can't be fucked anymore. For me, both, depending on the scenario of course.