Walking through a doorway makes people forget things. In experiments by Gabriel Radvansky and colleagues, people who carried an object from one room into another remembered it worse than people who carried it the same distance within a single room. The likeliest explanation is that the mind treats a doorway as the edge of an event: it files the room behind you as a finished episode and opens a fresh one, and whatever you came in for gets left in the old file. So standing in the kitchen wondering why you came isn’t your memory failing. It’s your memory tidying up a moment too soon.