Efficiency · 05 / 07

Brooks’s law

Adding people to a late project makes it later. Newcomers take time to become productive, take time away from the people who train them, and every extra person multiplies the coordination channels.

communication channels = n (n − 1) / 2

Try it

Start the project and add people whenever you like. Try early and try late.

tap to add
People
5
Communication channels
10
Expected delivery
–
Without changing the team
–

Where it applies

  • Adding ten consultants to a migration three weeks before cut-over usually pushes the date back.
  • Reinforcing a contact center in the middle of a campaign makes response times worse while the newcomers learn.
  • Growing a leadership committee from six to twelve members more than quadruples the channels and slows every decision.

Where it comes from

Frederick P. Brooks Jr., “The Mythical Man-Month” (1975), drawing on his experience managing the development of the OS/360 operating system at IBM. He himself called it an “outrageous oversimplification”: it describes a tendency, not an exact rule.

Bring it to your organization

In my workshops and diagnoses we work on this and other principles over your team’s real flow of work, with your data rather than the simulation’s. See services or write to me.