How often you bet the flop after you were the last preflop raiser and it was checked to you. Donk bets faced are not missed c-bets.
Having raised preflop, you hold the initiative — a continuation bet keeps the pressure on and wins many pots outright when the flop misses everyone. But c-betting every single flop is a leak on boards that hit the caller; the best players size and select their c-bets by texture rather than firing blindly.