Halls of Reflection. 5 waves pass, we kill first boss, all is good. Second 5 waves, second boss, he kills us because of lol.
We start again, the second 5 waves restart. On the second wave our tank disconnects. After a few minutes we just vote kick and... we're screwed... We can't get a replacement tank because the LFG doesn't apparently support that. We can't queue for the instance because we're saved... I can see this as a source of great many frustrations.