You are kidding, right?
One example: Have you ever actually tried to change settings or preferences in any version of Windows (for the PC)? It’s a clusterfuck and it hasn’t gotten better. The problem is not that it is ugly, the problem is that it is a pain to use.
Windows 7 has done many things right and is pretty awesome in many respects but there are important areas where its usability cannot reasonably be called good.