ESPECIALLY on Windows.
Some programs (cough, Adobe) will literally black out your screen and it will be a lone install prompt. Way to push your way to the front of the line.
Or it’ll just be consistently trying to pop over what I’m working on or WORSE! just flash in my taskbar like a needy little shit. Like, okay, I see you, got it, in a sec. Okay JUST GIVE ME ONE DAMN SECOND.