For me it's getting groups together, especially in the group finder.
Having waited forever to get a group together, we see a set of names pop up on the side of the screen. Awesome, time to actually play this MMO like an MMO! We stop what we're doing and head to the nearest Wayshrine. Sure, we could be lazy and just wait until someone else gets in the dungeon and teleport to them, but we're feeling supportive tonight and we'll take one for the team.
So there we are, sat in Darkshade Cavern, just need to wait for everyone else to pop in.
Any second now...
Send a friendly notice over PSN, (non PC master race) to let them know they can port to me.
10 minutes later and we're still pacing in circles waiting.
Give up, leave group.
This happens far too often. All group finder needs is an auto-teleport once your group is full.