The schools officers go to aren't any better than the schools NCOs go to. A year's hard work by the troops can be destroyed because of some minor incident that happened to the Colonel when he was a lieutenant. Officers sit around thinking a lot. In a vacuum. This is not a good thing.
Officers think they're businessmen.
This is because officers spend a lot of time trying to sell things, usually grand ideas and catchy names. Officers really do believe that a soldier is happier when he's busy, even if he's not doing what's important. NCOs know that nothing is so useless as doing well something which should not be done at all. There are a lot of officers out there who would have been better as NCOs, and a lot of NCOs who would have been better as officers. Creating a twenty-minute slide show that makes the commander look good will get you the same medal as working your ass off for 12 months for the same commander.