What aspect of gameplay is your biggest pet peeve?

RPG/Game Maker tilesets/graphics/resources, etc.

Having a much more direct method of doing things or going somewhere yet not being able to because 'game logic'.

Too much bloom that can't be adjusted (Syndicate 2013) is also a pain.

Enemy "health".

Unskippable tutorials

Walking through difficult mazes. In extreme cases, it can even overshadow the otherwise awesome plot. The Legend of Sword and Fairy 3 Gaiden: Chapter Regarding Love is often referred to as Chapter of Asking for Directions by fans because of its epic mazes.
How can we even solve these (fan-made maps for the mazes)? Note: Only a small portion of the scene is visible at a time and there are random battle encounters about every 10 steps.

dumb dialogues

backtracking all the way

Boring And unskippable random encounters(or that you can´t skip without loosgin a LOT of turns or life-like FF-), what is the problem with this, that you can explore nothing without a RE appearing AND the RE is not challenging enough to be...at less a resource killer(for example Dragon quest III you have a lot of RE, but your magic IS a really hard to fulfill resource(they are 2 o 4 items in the entire game that do that), and your inventory is limited so you have a limited amount of healing, making every RE a resource killer in your party...that add to the dread dungeon experience-almost that you got the magic items, that are expesnive and hard to find-. Now FF VII, your resource are...almost unlimited, your inventory is almost infinite, and yhe money is really rare that you got 0GP...yyeah....good luck RE to low my resources). I am a really patience player, but when one or more system get into the "main thing" of the game( FF the Random encounter and not so fun and repetitive battle system, when i am interested in the history...yeahhh, or a action game that put puzzles...because...puzzles!!!, or a FPS with platformer sections-and no a classic FPS, nothing like mirror edge or something like that-...), i know that you need to put this thing because you need make some "rest" to the main thing(like god of war...the best use of puzzles to dont make the action monotonous or boring...that in contrast make the action fell more awesome :D), but sometimes is used too OFTEN!!!.

Red Faction: Armagg..... i meant. repetitive play, but the worse probably, small variety of enemies.
rescuing and guiding stupid AI controlled characters.

And 1 more thing. to be forced to lvl up like crazy since i arrived where i shouldnt have before time.

Long unskippable cutscenes right before bosses. Oh you lost? Can't fight the boss again for 10 minutes because of this stupid cutscene!

QTE's, I'd kill the person who invented this shit.It's 2014 and some retarded lazyass developers still do that."Rise" is the newest game with retarded QTE's,I want to punch Crytek Devs in the face for doing that.

being compelled to loot random boxes/chests

not being able to have the option to keep progress when replaying game

most anything timed