When P.T. Barnum opened his museum of curiosities, he found that people were staying too long and not making room for the newcomers. Leary of making people mad by herding them out, he had a great idea. He had a big sign that said "TO THE EGRESS" that pointed to a door.
Well, of course, everyone was eager to see the Egress, whatever the hell that was going to be, so they pushed through the door. They then found themself outside in the alley with no way to get back in. He wasn't lying......that was the door to the egress.