General “Jumping” Jack Singlaub had an interesting take on this in his book “Hazardous Duty.” As I recall from reading it some time ago Singlaub was briefly in the Pentagon and working on personnel issues. He said their way of reducing officers was taking out all the good ones which would later force them to promote unfit officers. He used Lieutenant Calley as an example.
A very good book on the officer corps in Vietnam
written in 1978 by 2 Army Majors. I believe nearly all of their reccomendations were eventually implemented. Hard Hitting and Powerful, still have my original copy. ( and ain’t ever selling it )
Amazingly available on Amazon for $16 which suggests the military leaders still use it for guidence. Link to Amazon
https://www.amazon.com/Crisis-Command-Mismanagement-Richard-Gabriel/dp/0809001403