That doesn't work too well when, while closing the door, you lock a kitty in the room. Because you know as soon as the kitty realizes the door is closed, he is going to want to get out of that room. So it's not my fault I threw my entire body weight against the door so that she would wake up and let me out. It's his fault.
You should also know that if you close the door after letting the kitty out, that not only that kitty but the other kitty, too, will want back in. They might be really patient and not bang on the door, but waiting right outside the door. So don't be surprised when you finally open the door if there is a mass of kitty right there for you to trip over.