For me when locking doors and windows, or switching off lights, I have to check it about a zillion times. I check where my keys/phone/purse are at least 3 times per hour, consciously or subconsciously. I basically have a compulsion to check things constantly, bit of a worrier. It doesn't half get me down as well, like I have to plan going out 15 mins before everyone else, to allow checking time in my room before leaving :|