Being exhausted is not a reliable performance metric.

Tiredness measures the cost of a day, not its value. You can be depleted by work that mattered and equally depleted by work that did not, and the feeling is identical, which makes it useless as a guide. Treating it as evidence of contribution quietly rewards inefficiency.

At the end of a hard week, look at what actually moved rather than how you feel. If the two do not match, the fatigue is telling you something about your arrangements rather than your effort.