Earlier quoted context omitted.
You've mentioned Windows 7 twice in this thread. By what measure do you consider it a failure? If anything, Windows 7 is the best thing released under Ballmer.
Windows 7 is not a success. It's just a non-failure. The only reason people use it at all isn't because it's fantastic, but because it's incrementally better than Windows XP without all the garbage Vista foisted on the user. After having used it for an extended period of time, the only real improvements I've seen are in the explorer shell, which are minor at best, and the theme.
So last I heard there were 630 million licenses of Windows 7 sold. Even at OEM prices, that's 63 billion dollars of revenue. If that's not success, you're probably setting the bar too high.
>"The only reason people use it at all isn't because it's fantastic, but because it's incrementally better than Windows XP without all the garbage Vista foisted on the user."
That's a pretty broad brush you're using there. Really, that's the ONLY reason?
And what's wrong with incrementally better? The iPhone has only been incrementally better since the first version, and that's even more true of the 4s to 5. The iPhone 5 is still a fantastic phone! Amount of change from prior versions is a poor measure of quality.