It's more an annual flush, which is far more commendable.

When I bled mine ferociously several years ago I used a pal with a foot, Motive and one way bleeders across the week I did the dirty. I don't know which one finally got all the air out but the pedal drop was two inches and then it was a wall.

You need to ensure you have this feel in the pedal. If you don't there are air bubbles. Each time you address a re-bleed or flush, pay close attention to the exit stream. Forget the hose, watch the stream at the bleeder. I will bet it spits air a little only because time will dislodge cooties, not because you did it wrong last year.

I flush my brakes annually. When ATE Blue was available, I switched between them. For my farthest caliper it took about 200 ml to fully change color. Now I just do about 175-200 ml per.

15 to 20 was all I would risk doing before checking the reservoir. Quit this method and went to the motive when my MC gave up (of course it was 25 years old) so decided why risk it. I have done a few minor very careful pumps since when my pedal feel was not all I wished it to be after caliper rebuilds. Still need to know how to do this for your brake maintenance tool kit.

I'ver never heard of anyone bleeding or flushing their brakes with a certain number of pumps. Get the Motive.

I have a Motive but use it just as an air pressure source. Way back I tried using the Motive as both the pressure and fluid source - somehow I made a big mess of it and don't attempt that any more. Using as just the air pressure source is a lot of taking it off and on/etc. to keep the reservoir filled.
I now use my son as the pumper. This gives us additional bonding time and he gets the idea to do this on his Honda. I'm thinking the foot pumping method with rapid release at the caliper might "clean" out the old fluid better because of the high fluid flow rate compared to the Motive method.