Why C.P.M. method of scheduling is preferred to bar charts? What are limitations of bar chart?

C.P.M. method of scheduling is preferred to bar charts as a complete overview of the whole plan is offered, which makes it easy for the management to follow.

The following are the limitations of the bar chart:

• Progress of work is not shown.
• It lacks a degree of detail.
• It is unable to depict the interdependence of various activities clearly.
• It can’t differentiate between non-critical and critical activities.
• There is no provision to account for uncertainties of the time.