Management is the group of workers in a firm who are responsible for planning and coordinating the work that is done by the other workers. The managers, in general, do the thinking while the others do the work.
Management is very important in any business that has more than just a few workers. The firm's work must be planned so that it can go smoothly and efficiently. The various parts of the process must all be coordinated so that there are no hold ups in the process. In addition, goals and long-range strategy must be decided upon.
So management is very important to any business above a certain size.