If you formatted a harddrive to NTFS (maybe from a windows machine), and you plug it into Mountain Lion, open Disk Utility app. Lets say you want to format it into ExFat (the FAT32 successor). But you want security by wiping it to zero first during the format. Guess what? You can't do it. Each time you select "zero" the drive in the format options, and try to Erase the drive to ExFat, it fails. Why is that? Apparently, no-one tested it before. Another bug. How do you get a workaround? You must format it WITHOUT any security (no zeros, no DOD security of wiping 3 times, etc). After you erase it without any security, then magically, the security options work. (you can "zero" the drive, do DOD security erase, etc). There are LOTS of bugs crawling in OSX Mountain Lion that NOBODY fixes. Just slides under the rug release after release. Before, they may have less money, and you can get away with minor bugs not being fixed, but now that they are flush with money, continuing to ignore quality means something is wrong with their process.