[Annoying Trope] The character is at their lowest point in life, and everyone is treating them like an incompetent joke
When the character is at their lowest point, from guilt of failure or loss of everything, it annoys me that other characters simply treat them either as a liability or a joke that isn't competent enough to do the task given. Even more so when it's established that they are still capable of doing the tasks given.
Thor in Endgame: Having immense guilt for not being able to stop Thanos on time after losing everything he ends up being depressed to the point that he ends up letting himself go. From there, a lot of the characters treat him like some useless fat mass who isn't able to get the job of saving the universe done (Tony is probably the only one who rationally tells him that he's not in the best state to do a task that without insulting him).
Peter B Parker in Spider-Man: Into the Spider-verse: Divorced, broke and dead aunt added into the mix, he's at his lowest point in life and all the while everyone nearly dismisses him when they first meet him seeing him as a bad mentor. Although it does eventually get better as he did start getting his act together and doing a decent job leading the group.