Checks and rechecks the door lock 5 times before leaving the house
Explanation:
He checked the lock 5 times to be sure he did locked door. "5" times here is extensive, at least a maximum of 3 times of checking before leaving I.e if he had a lot to do and he just needed to be sure.
The act of him checking more than 3 times is an sign obsessive compulsive disorder.
