One other disadvantage of having too managers is that it leads to a reduction in organization productivity. Each team reporting to a manager eventually becomes a silo. A team only works on the tasks assigned to it by its direct manager only. This results in some teams which are overburdened, while the team sitting next to them doesn't know what to do with their time.

The managers are too busy in their daily meetings to figure out what is happening on the floor. This causes lot of resentment in the teams.

If a project gets assigned to a manager and the best resources to work on this project are on some other team, it is really tough to pull them in to work on this project. This results in reduced overall efficiency as teams have been artificially divided to create a reporting structure for the manager.

I understand that some of you would not have seen this type of manager in your work life. But I am speaking from my own experience and recognize that there are managers which are very good. But I have seen too many of them coasting along, doing little real work while increasing the organizational inefficiencies.