I don't agree on your examples : - teachers : if you have let's say 30 students, you need one teacher, in you have 300 you probably need 10 teachers. I don't k

I don't agree on your examples : - teachers : if you have let's say 30 students, you need one teacher, in you have 300 you probably need 10 teachers. I don't know how can you one person deal with 300 students giving them the required attention. Since you have the school program you can start paralyzing the tasks. - doctors : If you have 10 sick peoples... 1 doctor, with 100 you probably need 10 doctors. A doctor need time with a single patient to study the case. There is probably plenty of good examples, but not that ones. About building softwares, even if you pick the right guys and split the task properly (which requires peoples, time and a high level of understanding) and let peoples work on their own, you lead to inconsistency. Splitting an existing task to add new developers and save time requires redesign and headaches to avoid incompatibilities, probably breaking new things or requiring some rework in the work done by the others.