If the door is unavailable, stop spending the entire day studying doors.

When one route is closed, attention tends to stay fixed on it, and you can spend a great deal of time examining an obstacle that will not change. The energy is better spent looking for what else exists, which requires deliberately turning away from the closed thing.

Give yourself a limit on how long you will study a blocked path. When it expires, go look at the walls, the windows, and the people who got in another way.