People "falling through the floor" and getting stuck, without being able to be ressurected.
Also; when people accidentally drop off of edges they often have to leave group - get teleported out - and then get reinvited just to come back alive.
The gate by Ozara which spawns Overchargers (presumably a similar problem exists for the gate across the hall) can permanently trap players.
I think it is central to ESO's well-being to critique the developers when they change the game (or fail to change something).
But the negativity can be exhausting, so I vow to post 50/50 negativity and appreciation.