Brooks's Law - Adding people to a late project makes it later
When a project is behind schedule and more people are being considered
What Does “Brooks's Law - Adding people to a late project makes it later” Mean?
New team members need time to learn the project, and they take time from the experienced people who must train them. Every extra person also adds communication paths. So adding people to a project that is already late often delays it further, at least in the short term.
Origin and History
Fred Brooks, who managed IBM's OS/360 operating system project, stated it in The Mythical Man-Month (1975): 'Adding manpower to a late software project makes it later.' Brooks himself called it an 'outrageous oversimplification' - it applies most strongly to complex work that is hard to divide.
Examples
- Software: adding five new developers two weeks before launch.
- Construction or events: bringing in extra helpers who need constant instructions on the final day.
- Contrast: tasks that divide cleanly (stuffing envelopes) do speed up with more people - see 'many hands make light work'.
What Happens When You Break It
Ignoring it leads to ramp-up time, more coordination meetings, more mistakes and an even later delivery, along with a burned-out core team.
Benefits of Following This Rule
Understanding the law leads to realistic planning, small focused teams, early staffing decisions, and honest trade-offs between scope, time and quality.
Frequently Asked Questions
Is Brooks's Law always true?
No. It applies to complex, tightly connected work with a long learning curve. Simple, divisible tasks do get faster with more people, and adding people early in a project is far less harmful than adding them late.