It pays to have a keen eye!
...except if you're a mole of course, in which case it's fairly useless.
I am a mole and I live in a hole. I've lived in this paricular hole for a short while, I couldn't tell you exactly how long, the passage of time is hard to gauge when you live underground. But let's just say us moles move around a lot, so you never know where we'll pop up next.