What are some things that just get under your skin about games?
For me, it's games that do not allow controller rebinding. I have neuropathy and my fingers don't all work. If I can't rebind buttons so that I have necessary moves (for example: parry) be on buttons I can reliably press the entire game becomes unplayable.
And on console, where I can't refund a game after I downloaded it (fuck you Sony) then it really screws me over wasting what limited funds I have on games I just can't play.
Showing a long plot-explaining intro right after start, before I have a chance to get to "options" and set the resolution, subtitles, etc. I also "love" unskippable short logo videos at start. And a few screens with only "press any button to continue".