A general or other leader doesn't have to learn about all that in detail, he simply knows the system works and how to utilize it for his purposes.
Logitics defines what is operationally feasible. Without a fine appreciation of logistics, that comes from detailed knowledge the commander simply is operated without knowledge of what is operationally possible,
"Bitter experience in war has taught the maxim that the art of war is the art of the logistically feasible."
- ADM Hyman Rickover, USN
"Amateurs talk about tactics, but professionals study logistics."
- Gen. Robert H. Barrow, USMC (Commandant of the Marine Corps) noted in 1980
"Only a commander who understand logistics can push the military machine to the limits without risking total breakdown."
- Maj.Gen. Julian Thompson, Royal Marines
"In modern time it is a poorly qualified strategist or naval commander who is not equipped by training and experience to evaluate logistic factors or to superintend logistic operations."
- Duncan S. Ballantine, 1947