No upward momentum. The HR policy is (seriously) to NOT give people a raise when they're promoted until they've been doing that job for 6 months. It gives no incentive to do well and get promoted. If you want a promotion(and wish to be actually paid for what you're doing), you have to leave the company. They said that "this is for the employee to see if they like the job" but nowhere else that I've worked does this. It's a terrible policy.
Hired from the outside? Great, they'll pay you what you deserve.
Promoted from within? Too bad. No raise for 6 months. No incentive to do better work.