The concept is known as "Career Corporals"....there is a kind of guy that is exceptional at his war fighting job....fights wars...get the job done that he is assigned...does it well...and on time...and never gets promoted to his true and just deserves.....because then he would not be around to accomplish what needs to be done.
The pencil pushing...stroke the boss....kiss ass who does the Boy Scout thing not for doing good deeds for the young ones...but merely for the brownie points it brings him...are the drones that get promoted.
War fighters always get the short end of the stick....in a peace time military.
