Harry Truman said generals make lousy presidents—too much pride and they aren’t used to having to take orders from those they lead (citizens vs soldiers)..
Ike wasn’t too bad but he could have been better and Harry hated him.Still,there is a point there—look at Grant.
Conversely . . . I suspect the ranks of the military are filled with a lot of "yes men" who have never had an original idea in their lives.