We all know that small teams work better then big teams, and there is even a study.
But what are the limiting factors of big teams? why do they do so poorly compared to small teams?
a 32-person team on average would have used 178 person-months of effort ($2.1 million at $12,000 per person-month). The 4-person team would have used 24.5 person-months ($294,000 @ $12,000 per person-month).
How much schedule compression was achieved? Not much! The difference between the large team and the small team approaches for the average project of 100,000 source lines of code is approximately 1 calendar week.
In the study results, we can see that it took the big team (32 developers), 1 week less to complete the same project then the small team (4 developers), this 1 week difference seems to be too small for it to be luck, but it just seems too small.
We are talking about 8X developers working on a project for 9 months, and the only difference is 1 week.
So what is it that limits big teams from doing much better then small teams? I don't expected 50% less time if you hire twice the developers, but I do expect a much bigger difference then just 1 week (out of 9 months).
Is it management? Communication?