Vantaggi
Some people really do get the opportunity they promise - its just a very small percentage, and frequently people who are good at getting to mgmt, and then feel entitled to take perks for being where they are. I was one of the few who got a really amazing opportunity, and I dont regret working there, but I learned a lot about what can be done better.
Svantaggi
Because all entry level people have to work long hours for very very little pay, they do the brunt of the work. The managers are opportunistic, and part of their corporate story is that you get to have more flexibility, more pay, and better conditions once you get to management. This encourages managers to slack off, and frequently incompetent people who are good at working the system get promoted.