Lazy brain

Why is my brain so lazy?  Sometimes to enter my place I start checking each one of my keys in sequence, instead of thinking which one is the right one.  This happens when I'm tired and I start applying the most stupid algorithm, the linear search.  Sometimes it's easier that way: 33% chance is a pretty high number, if I'm lucky I'll solve my problem with no brain power, and if I fail no one dies -actually- on my second trial I'll have an even greater chance to succeed: 50%.  Worst case, my third trial will be 100% guaranteed to succeed.  Not smart but certainly a way to get things going...