When I was training for 1st Kyu I got into a lot of trouble at work.
We had swipe cards to open the computer room door. 9 times out of 10 they worked fine, 1 time out of 10 you had to reswipe. As the door was big and heavy, I got into the habit of dropping my centre and moving *through* the door - very Irimi.
I went through 4 locks in about as many weeks.
My excuse was that if a 9 stone weakling like me could accidently break the lock what would happen if someone seriously wanted to get into the computer room.