Look at the Army WO1/2 with about 6000 compared with the RAF WO/MACR near 1000 and the RN at the same.
If we look at boss worker bees - fofl/fs/wo equivalents we have:
Army 19800, RN 12520 and RAF 10040.
At sqn ldr eq it is 4470, 1020 and 2980.
Percentage wise, the OF4 grade in the Army is 22% of the managers grade, in the RN it is 8% and in the RAF it is 30%.
Clearly the RAF has more execs than managers whereas the RN promoted or out seems more efficient if more brutal.