I think the value of Vote Abandon is proportional to the number of players in an instance. From my personal experience, with four player instances I can almost never recall it being used successfully in a way that wasn't self-serving by a couple of people who had entered together never intending to complete it because they were trolling or just trying to cap a certain kind of tome partway through. On the other end of the extreme, when it's succeeded in 24 player content I've pretty much always been in agreement. If >= 12 out of 24 believe it's hopeless... it's probably hopeless. Sure there's the one off person who gets the loot they want, vote abandons after a wipe at the next boss and leaves when it fails... but that's why it's a vote after all.
