Partial somnambulatory maladroitistic dementism?
Most Catholic geezers have at least one memory of (themselves or others) walking into a theater and genuflecting before taking a seat (as we used to genuflect before taking our seat in church).
Bad enough spraying antiperspirant into your hand.
Imagine the joy of spraying shaving cream into your pits.
Here’s a recent MPSIMS thread on exactly these sorts of errors: http://boards.straightdope.com/sdmb/showthread.php?t=282412
It’s not about the why’s, just the what’s, but it’s interesting to see both the variety of screwups and also the consistent patterns.
It appears many people spend a lot of their day doing one thing while thinking about another. Those semi-autonomous processes aren’t nearly as robust as we think they are.