1)Managers organize and integrate people. They bring objective to the people responsible for some jobs. Managers should be able to make people to work as a team. They should organize and supervise the jobs of their subordinates as well as to work with them themselves.
2)Managers should be able to measure the quality of the performance of their team as well as estimate whether the objectives set can be achieved.
3)The last but not the least, managers should develop both themselves and the staff they are working with.