The definition of a manager is a person responsible for supervising and motivating employees and for directing the process of an organization.
But what really makes a good manager?

In order to be an efficient and respected manager one must have confidence, how can you manage and lead other people if you don't trust yourself? To be able to lead you need to be confident and talk confidently.
Another characteristic of a good manager is thoughtfulness. Why? As a manager you have to be thoughtful about the needs of your subordinates, put yourself in their shoes. Be thoughtful of their strengths and weaknesses in order to maximize their potentials. Always value them, because they are a part of your team and a team cannot function with one member missing.
"A key to achieving success is to assemble a strong and stable management team" - Vivek Wadhwa