Why do all system manhwa MCs choose a dagger as their weapon?

This is so such a non-issue and not that serious but, why do MCs always choose a dagger as their main weapon? out of all the weapon choices, they have like; a scythe, sword, or a GUN, they choose a dagger. and don't get me wrong I love dungeon/levelling/systems manhwas. I eat them up but, it just makes me laugh. and most of the time their reasoning is it gives them aura points like. Anyway, that's my unserious rant!