I was looking out of the kitchen window this morning at the rain. It looked like it was just on the edge of being sleet. A few minutes later I looked again and it now looked more like sleet on the edge of turning to snow.
A few minutes later, I realised my glasses were not where I was expecting, beside the bed. I started to try to figure out where they could be. Suddenly I spotted them on a piece of furniture. And was disappointed. I caught that disappointment as I have sometimes in the past: oh, it was that in that moment, trying to figure out where the glasses were had become a satisfying puzzle. Finding them by accident spoilt the fun, even though ostensibly the point was to find them. A few minutes later, it would have been a different story.
Margins and edges are interesting places.