Some universes have methods by which scars can be removed and serious injuries reversed. Warcraft has many different kinds of healing; even the Undead can get a Shadow Priest or Necromancer to repair their body. But, it is very annoying in settings where there's no excuse.
An even more extreme form is people who take phenomenal damage, but are back up in five minutes and dandy when you see them the next day. We have this in spades on my server, sadly. There was one elf who we literally formed a small army just to kill, because he was such a bad roleplayer;
we shot him full of shadowbolts, set him on fire, struck him with divine lightning, blasted him with a laser canon, and shot him numerous times with magical bullets. One of his equally-badly-played buddies resurrected him not five minutes later.
There's another peeve of mine; resurrection is not cheap! Not even in Warcraft. A Necromancer can bring you back on short notice, but only as a horrible decaying corpse which constantly trips over its own loose entrails. A real resurrection takes work, hard rituals which can easily backfire, and probably a long quest. It's not something that should happen every day of the week for vile marty stu Elf-whatever-it-was-I-don't-remember's.
And then we have the idiots who claim to be the master of their chosen occupation because of training in a poorly-written backstory, or something. Often, these people don't even do any research or show any signs of practice in play. Mages have to actually study their spells and work to commit them to memory. Archers need to practice and there -is- a right way to hold a bow and fire it, contrary to popular ignorance. Warriors need to exercise and practice to remain strong and skilled, but I somehow never see bored warrior characters typing out an emote (the way we express character actions on WoW servers) about doing a few quick exercises while they're waiting. You know you have lifestyle issues if you're too lazy to even roleplay physical activity! O.o