On some engines, the oil pump is above the oil level a good bit- Cummins, some Detroits, some others.. And grinding away at the starter may spin the pump so slowly that it does not pick up a prime. Those pumps will not pump air very low rpm, and they need to pump air to draw in the oil.
I've been called out where someone was cranking while holding stop and waiting for oil pressure to rise. crank, crank, crank, crank. Pressure never comes up. I come and check things out and simply start the engine. Pressure comes up in five sec.
I don't think cranking while holding stop is a great idea, unless on your particular engine the pressure comes right up. Bearings are wet with oil even without pressure, and it takes relative velocity of the surfaces to create the oil film. 15sec of slow rpm on starter could be worse than five seconds of engine running. Pumps prime faster when you spin them faster.