Most of the managers that I have come across are not worth the paper on which their job description is printed. I am talking about the middle level managers here.

There is some adhoc planning going on at this level but most of the time it is dictated by what is being conveyed from the top. This takes care of all the planning, task assignment work. If the manager has capable team members then all that is required is to just tell them that they are now going to work on project X. After that it is the responsibility of those team members to manage the work. All that the so called managers do is check periodically about how it is going.

Recruitment of engineers is again completely left to senior engineers. Once 3 senior engineers say yes to a candidate, the manager just has to complete the formalities. So there is no contribution in building better teams.

There is no technical input from the managers as this takes lot of time and is somehow beneath them.

With agile processes, the team manages their work flow on a day to day basis. So the manager role is reduced even further.

All they work on is performance review once a year. It is more of a give and take as the manager and his manager don't have any realistic idea of an individual's contribution.

I think time has come to cull the managers rank and just have 1 manager for 100 developers with developers organizing themselves in self-managing teams. The managers just get too much credit and money for doing essentially nothing.