I've certainly got my own issues with 10, but it's not terrible. It's certainly more stable than XP, which is where I upgraded from. One of the important things, as was mentioned, was disabling automatic updates. I slept in on a cold Saturday morning a couple of years ago, looking forward to a cup of coffee, a muffin, and some gaming, and found that Windows had updated overnight and completely nuked my VGA drivers. That one's a bitch to straighten out, I'm here to tell you. That was it for Windows update.
Disabling Windows update is a fine example of why I hate Windows 10. Microsoft won't let you do it because you're not smart enough. It won't let you do anything that MS thinks isn't in your best interest, and it's infuriating. I had to install a specific registry hack just to be able to delete files that MS claimed ownership of. I built this computer and I installed the OS. If I want to delete the entire fucking registry that's between me and my gods. It isn't any of Microsoft's business. It's really become quite HAL-like. Any time I install W10 I always spend a couple of week cursing the various things it won't allow me to do to customize it to my liking, and hunting down the various tweeks and hacks that I last used years ago.
And there are a few things that have either gone away or been "improved" that bug me. The W10 volume mixer is terrible. Same with the clock and calendar. Every time I turn my TV on or off it scrambles all three of my displays because it's no longer possible to disable autodetect, and Windows' multiple monitor support is weak. Windows calls this a "feature."