Adding manpower to a late software project makes it later.
Brooks's 1975 observation from IBM's OS/360: new people must be trained by the productive ones, and communication paths grow as the square of team size. Nine women cannot deliver a baby in one month.
In practice
- Three developers join a project six weeks from delivery, and the two who understood the system spend those weeks explaining it.
- A restaurant hires four staff on its worst night and the kitchen slows, because the head chef is now training rather than cooking.
- Further reading
- Wikipedia
- Subject
- Technology & Software
- Essay
- The curves, the limits and the laws of software