Allot of people don't seem to respect their tank, even when they are constantly pulling aggro off them.
A while ago, I had a ToC heroic group on my half blue half epic geared tank with 26K hp/545 defense.
We wiped a couple of times, and I got booted while I kept perfect aggro, while the Healer was utterly shite.
I believe this is one of the reasons people hate tanking, they have to take a crapload off bull-shit over their head tbh. Lately I haven't been tanking for pugs anymore, I'm only tanking for guildy's and friends now.