Any particular mechanic you just can’t stand? Lack of mechanics applies too.
In my case, there are:
Hitting an enemy being based on RNG in Morrowind.
Not being able to replay stages with any character in Devil May Cry 5.
Heat in Tekken 8.
The main character dying while the rest of the party is alive in an RPG meaning an instant game over.
Unskippable cutscenes, your plot ain’t that good, bro.
Unskippable tutorials, specially if they’re tied to the story. Again, your story ain’t that good, bro (looking at you, BOTW and TOTK)
Unskippable start screens.
Quest items being in your inventory after they’re already used.
NPCs walking faster than your walk speed during conversations but slower than your run speed.
Hard mode lazily making enemies tankier.
Fighting games without good training modes (lack of frame data and hitbox displays, no recording options, etc.)
Being found once during a stealth section meaning an instant game over.
At the same time, poorly implemented stealth AI.
Also also, being found somehow means everyone else in the playable area knows where you are.
Having to wait IRL time for an item to craft.
Crafting in games that don’t need it.
Running using stamina outside of combat.
Only being able to sprint for like 3 seconds in horror games.
NPCs telling you to hurry up when the game puts you in an area where there might be stuff to find.
Making it mandatory to win a boss fight just so you get sonned in the cutscene anyway.
Tripping in Super Smash Bros Brawl, you have 1% chance of tripping each time you run and 1.25% when you turn around while running and, if I recall correctly, you have more chances of tripping the better you’re playing. Literally zero reason for this mechanic to exist other than to annoy players.
Long death screens. Ninja Gaiden 3 might have been booboo, but one thing that game did really well is that they completely removed the game over screen. As soon as Ryu dies the game fades to black and fades back in with Ryu alive at the checkpoint.
Being able to get hit while in the middle of animations such as executions (looking at you Bloodlines 2 and Space Marine) climbing objects, etc.
Dark Souls, Bloodborne and Elden Ring not having pause buttons in offline mode.
Only one save slot.
Not being able to kill important NPCs in some RPGs, instead just “knocking them out.” What happened with still being able to play but if you want to continue you have to load a save file?
Choosing a job that’s considered “evil” in RPGs, for example Necromancer, immediately locking you out from making a morally good character. (Let me be an ethical Necromancer, please!)
Make the same button do different functions.