We have a water cooler at work, with those big water jug things. When you go to get some water and the jug is empty, you have to replace it; this probably happens 2-3 times/week.
I encountered an end of a jug (and therefore replaced it)
three times in my first two weeks in the lab, and then I didn't
encounter one again until this morning, nearly a year later. My brain immediately started trying to read meaning into this. Why then? Why now? Why not all the time in between?
The reason, of course, is "just because". If I
ever create a course called "Psychology and Statistics" (spoiler: I
won't) you can be sure there will be a segment on water coolers.