Driving to my haircut appointment, I thought I'd be about two minutes late, so I used my trusty cellphone to call and announce my tardiness. Of course the receptionist said "no problem." That left me trying to explain to myself why I had bothered to call. Why call to tell anyone I'm going to be late by such a small amount?
It turns out there's a good reason, at least in my case. As soon as I made the call, I relaxed and started driving more slowly and carefully.