-Leaving clothes in the dressing room and off the hangers pisses me off.
-When a customer is giving me a dirty look, because I'm straightening the racks.
-Or after I straightened a rack, a customer decides to mess up the rack again by leaving various clothing items sticking out.
-When a customer decides to bitch and complain at the total.
-I also don't like it when customers arrive at the last minute. When 9:00 rolls around, I'm usually, along with whatever manager is on duty, ready to leave.