Pamac.
I like it. It's simple and better than that "discover" software center thing.
But omg do I hate pamac. Not even talking about what it caused to the AUR. I'm talking about automatic full system updates.
It's so annoying. I'm working on something, have like 20 open windows where I'm doing something. I just need that ONE app to continue. So I install it using pamac, boom. 2GB of updates and I can't even skip it. Alright, I wait.
When it finally finished I tried continuing with what I was doing, but nah. Some nvidia driver update broke my stuff and I have to reboot my system.
That's very annoying. Remember, I still have all my work open, including one app which takes a stupid amount of setup when starting. I really don't wanna have to reboot at that point. But I have to.
So I open the "windows button menu" (don't know the name, but you know what I mean) and click restart. It gives me an error. Probably updated some critical thing relating to the reboot menu which broke it.

(I know I can just use the terminal to reboot, but before I do I had to make this post.)

This isn't a one time thing. This has happened to me twice before. What really makes me mad is that I can't turn full updates off. There would be a really simple fix to all of this:
When installing an app, check for updates and just ask the user if they want to update everything, or just install this app now (and update the dependencies for it).

I understand that I have to update my system, but just let me finish my work first, okay? Just update when I'm done. It would also be nice to have an extra button for "Update and shutdown" without going the Windows route and forcing updates.
While I'm on the topic of windows, I used Windows 8 once on a laptop belonging to a family member. I was in the proccess of doing something when it just blacked out, stopped all apps and started installing updates. Not even a warning. That's just one of the reasons I'll never even consider switching to Windows.

(Using Arch with KDE btw.)