Another reason is updates that improve user experience. While it might sound like a good idea, after all this time, reading “improve user experience” just means one of two things: on a console that's just another update designed to hinder the execution of homebrew, user-written software for consoles. On a PC that just means they're again moving some buttons around, and I need to waste my time finding where the button I need has gone and getting used to it new place again. Just so it might move somewhere else with the next update. Over time, I have come to appreciate stable UI and command-line tools that are primarily designed for script execution, so it doesn't change much with updates, saving me a lot of time in the process. It is quite ironic if typing in up to 160 characters can be much faster than searching for a damn button that does the same thing. But unlike most users, I'm tech-savvy. So here as well, frustrated users started to disable updates, so they can stop wasting time.
Another big reason is the fact that updates don't necessarily stick to their promise of fixing issues and/or adding new features. Instead, they actively break that promise. At times, updates just make the system even more unstable. Why on earth would I update if all it does is crash my system, sometimes to the point that I have to reinstall everything?! The fact that some companies just keep pushing unstable updates to their customers, just makes it a high-risk low reward gamble with every single update. So again, disabling updates seems to be a better choice. But then, a certain company just decided instead of pushing stable updates, they just enforce automatic updates. Well done, Microsoft! You are just the worst. Stop using your Home Edition users as beta testers!
And there's the problem that an update might remove a feature from the software or even add an anti-feature. You have never seen it happen? Sony's removal of Another OS on PlayStation 3 is a good example. I even had an instrument tuning app on my mobile where a feature was removed due to patent trolling. Or like how the current version of Skype is infested with ads. I could go on and on… the point is: it happens. And the only solution seems to be, again, not updating.
So why would you want to update if all it does is very likely to ruin your day? On a console, you are simply barred from using new software if you refuse to update. On a PC, getting infected with malware just ruins your day even a lot more. And the only way to stop that is installing updates.