Software Design X-Rays

Code Ownership and Diffusion of Responsibility

So far we’ve discussed coordination needs mainly in terms of quality: the more developers who touch a piece of code, the higher the risk for defects. But coordination also has a very real direct cost, which is what social psychologists call process loss.

Process loss is a concept that social psychologists borrowed from the field of mechanics. The idea is that just as a machine cannot operate at 100 percent efficiency all the time (due to physical factors like friction and heat loss), neither can a team. Part of a team’s potential productivity is simply lost. (See Group Process and Productivity [Ste72] for the original research.)

The kind of process loss that occurs depends on the task, but in ...