xkcd

IKR? Especially if they all start the room you can leave and the other room is small enough to be a crush when everyones in it. At first a few people go through the door out of curiosity but realize its one-way, some people panic some don't, some go in there too but it starts getting crowded. But now you have a minority outside the crush room who are being told not to come in and getting increasingly isolated. One by one everyone enters the crush room making everything worse for themselves and everyone else.