A traditional principle involves the span of control of a manger and states that there is a limit to the number of subordinates that one superior should supervise. This principle is stated in terms of the exact number of subordinates that should report to a superior and thus has become highly controversial.
The determination of the optimum number depends on many factors in a given organization and should always be tied directly to the question of the number of levels in the hierarchy. If it appears that a small span of control for each manager is desirable then the number of necessary levels will be larger than would be the case with a larger span of control. The organization with more levels will be “tall” whereas the organization with a larger span of control will be “flat”.
Span of control focuses attention on the basic fact that any human being has limitations. First, one has limited time available for one’s activities. Second, one has limited available energy and must depend on others to supplement one’s energy. Third, the number of subjects to which a manager can give attention is limited. These limitations not only support the concept of span of control but indicate that the optimum span of control varies among individuals.
Also, the span of control under one set of physical conditions will differ from the span under another set. For example, the problems of a military commander fighting in the desert differ from the problem of a commander fighting in the jungle. Improving communication devices may make a larger span of control desirable. The dispersion of necessary information may change the optimum span.
Span of control refers to the number of people that one person can supervise directly. A related, but broader and possibly more useful, idea is the span of managerial responsibility. It refers to the number of people whom one superior can assist, teach, and help to reach the objectives of their own jobs – that is, the number who has access to the superior. The span of responsibility probably can be larger than span of control.
The span of control principle does not resolve the conflict between the advantages of a “tall” organization versus those of the “flat”. It is evident as the number of levels increases, the number of channels through which orders must flow increases. Questions of span of control and number of levels must be handled concurrently in any decision about the structure of an organization.