While 9 mothers cannot produce a baby in one month, 9 farmers can harvest a field of cotton 9 times quicker. Why can you ‘divide and conquer’ with some tasks and not others?
Two main factors prevent a task from speeding up linearly when you add more manpower to it:
- When the task cannot be perfectly partitioned – A field of cotton can be perfectly partitioned. But sequential tasks that are interdependent cannot be partitioned without delays – e.g. writing the script for a video and recording it.
- When partitioning requires communication – Suppose that three programmers are writing a scheduling software that is (ironically) behind schedule. Adding two more developers requires communication. First, they need to be trained on what has already been done. Second, they need to coordinate among each other on a regular basis.
Adding more people may even make the problem worse. The number of information channels increases exponentially as team size increases. A team of two people has merely 1 communication channel (A-B), a team of three people has 3 (A-B, B-C, A-C) and a team of five people has 15 channels – n(n+1) / 2.
As managers, it is tempting to throw more people at a task that is behind schedule. But that doesn’t always help – especially while dealing with the two scenarios above.
Inspriation: The Mythical Man Month
Recommended Reading: Brook’s law