The checkmate usually started with a lazy move twenty turns earlier.

Losing positions get built long before they look lost. One move made without thinking, because nothing seemed to be happening, quietly removes an option you will need much later, and by the time the trouble is obvious the useful choices are already gone. The visible disaster is only where the earlier carelessness became unavoidable.

Pay attention to the moves that feel like they do not matter. The Tuesday assignment, the conversation you handled sloppily because you were tired. Those are the turns that decide what your options look like a month from now.