There is no universal perfect number. Early sets establish the repetition; short rests let later sets approach or reach the limit through accumulated fatigue.
Earlier sets should preserve the planned repetitions and target-muscle control. Later sets may reach technical failure as local fatigue accumulates.
Do not force unsafe failure on unstable movements. End or adjust the exercise when form, target-muscle tension, or the pump deteriorates.
Pump Ledger is a training logbook, not medical advice. Scale training to your experience and circumstances, and seek qualified guidance when health or injury concerns affect exercise.