Last week I was just about to enter a hotel. A teen exited from the heavy and large revolving door, and being a teen, he made sure the doors were spinning really fast when he left. When I was entering, I tried to stop it: I put my hand on one of the doors and tried to pull back.
Big mistake.
I realized the door was too heavy and still spinning rather rapidly. By the time I left my hand, the door was a centimeter away from finally entering the outside frame. I pulled away my hand just in time, but the shear weight of such a door coupled with the speed would have wiped out my fingers (there is no space between the door and the outside frame). I wouldn't know what would have happened.
In another instance, somebody closed a steal door (not common in North America) against my fingers. I went straight to the hospital as I couldn't move my fingers, but luckily everything was alright after a few hours. But a revolving door is a different story. It doesn't stop.