Let's face it: PvP certainly has quite a rep for intimidating and exasperating players. Not me, though. I'm totally down with PvP. The thing that throws me for a loop is the whole economy and Auction House thing. Despite editing Gold Capped after Gold Capped article during my time in the WoW Insider editorial chair, I've never managed to wrap my brain around strategizing how to make money in game. I use an AH addon strictly to help me get the heck outta Dodge. I want that stuff gone! Since much earlier eras, I've never been short on funds for anything I really wanted to buy, so my slapdash approach seems to serve me adequately. As a result, the inner workings of my AH addon and the realm economy in general remain all rather mysterious to me. I simply can't (and won't) take time to digest all that twitchy detail.
I have a friend, though, for whom playing the market is an amuse-bouche to any good play session. Unfortunately, his idea of a good play session and mine diverge at the point that it's time for him to move out of the fire -- his painfully evident Achilles heel. I have no idea how he hasn't internalized this basic by now, but there it is. He's just not a mover. I heal him a lot. We love him anyway.
What part of WoW's gameplay bedevils you to this day? Maybe it's something that took you more time than you'd have liked to master. Perhaps you're still struggling. Or maybe it's something that you've just never figured out (and possibly never want to). What's your WoW Achilles heel?