In Moscow... (Score 1)

In Moscow's subway system, you get a ding-dong sound warning you that the doors are about to close. If someone is still in the doorway while they are closing, the doors sense the pressure, and will retract for a second or two. they keep doing this until the doors finally close. no need for a conductor in the middle of the train to yell at you to get away from the door.

Once all the doors manage to close, the driver in front gets the green light and moves to the next station.