Because it's UNIX but without most of the shortcomings of other UNIX distributions. Also with the OS and the hardware made by the same entity, there is no fing

Because it's UNIX but without most of the shortcomings of other UNIX distributions. Also with the OS and the hardware made by the same entity, there is no finger pointing when stuff goes wrong. You don't have the card/board/device maker blaming the driver/OS/software authors and vice versa, so instead of a hopeless feeling, you have a system that works. Yes sometimes Apple is said not to own up to their own problems (keyboard-gate, etc.) but often there exists a PBKAC and there are a lot of haters out there who love to post exaggerated horror stories, so take all that with a grain of salt. It also has a bug reporting system that, while it could be better and doesn't give you much feedback, at least you know it is being paid attention to, and updates are improvements. Also you know the creators aren't out to harvest all your data, and they seem a lot less likely to be in bed with three letter agencies that would love to backdoor anything you write. Not thinking of Linux with those two points, but other players. Linux systems have their own problems (see finger pointing above).