Pay is low.
Everything from respect, to vacation, to salary, to promotions are based entirely on tenure. Skill seems to have no impact on any decision making. If you look around you'll notice there aren't any younger people there. That's because younger people leave when they realize it doesn't matter how much they know or how good they are at their jobs, only how long they've worked there.
Several layers of middle management do nothing at all of any use. As far as I can tell, their only purpose is to interact with each other. They certainly don't interact with the people doing the work. Obviously this means upper management isn't doing their jobs or verifying anything being told to them by middle management.
Attempting to improve anything requires change, and change quickly brings out fear from the long tenured employees who will then resent you for it and sabotage everything you do.
The office politics are brutal.