I agree with Jonny Dale. I will stay in an instance as long as it takes to get it done so long as there is not a clear reason why we are wiping.

I remember my first run through Nexus. I think we wiped on every boss at least once (and usually more), and we even wiped on trash mobs a couple of times. Do we suck at instances? Yes. Are we the kind of people whom raiding guilds want to have if they need someone to fill a spot? Probably not. But none of us got frustrated and we eventually made it through the whole thing. I got new boots and a new belt I believe, and it was fun. We may not have made it if Nexus had not been a brand new instance that none of us had done, but it still would have been fun for me.

Although I wear plate gear, I never worry about repair bills. The rewards from getting through the instance and completing those quests or getting that loot or getting that achievement always outweigh the repair cost in MY mind, and I can just sell a stack of Saronite and the bill is taken care of.

It drives me crazy when people leave without saying anything. Just the other day I was tanking heroic Violet Hold. Everyone else in the PUG was from a fairly new raiding guild on our server. We ended up with the purple ethereal boss, who is very hard on heroic. The leader of the group explained the tactic for killing the boss, which involves kiting him away from two orbs that he spawns. We ended up getting trapped on the upper level of the Hold with an orb on either side of us. I tanked us away from the closest orb, but then he yelled "TAKING WRONG WAY!!!" so I took his advice and tanked us straight into the other orb and we wiped. Everyone left. I know that it is Violet Hold and people don't want to do the whole thing over again, but I would have been willing to stay longer than we did.