players preventing the development of low-level characters
I play a warlock for the horde faction (at the time of writing, level 25) and as I progress through the storyline for the undead, I come across an alliance paladin who for a long period of time prevents the completion of quests by killing NPCs and waiting at the respawn point. The name of this paladin is Casshern. I have nothing against pvp in the world, but when it is + - similar levels without impeding the play of another faction.
Lorderon|Undwarlock in game|Horde