Quote from : Ender's Shadow Book

But in the military you don't get trusted positions just because of your ability. You also have to attract the notice of superior officers. You have to be liked. You have to fit in with the system. You have to look like what the officers above you think that officers should look like. You have to think in ways that they are comfortable with. The result was that you ended up with a command structure that was top-heavy with guys who looked good in uniform and talked right and did well enough not to embarrass themselves, while the really good ones quietly did all the serious work and bailed out their superiors and got blamed for errors they had advised against until they eventually got out. That was the military.