Software works differently to many other fields in that all devs need to keep lots of complicated technical context in their heads, which doesn't translate well to how managers experience scalability, as that field is just vastly different. It's also hard to explain to a non-programmer (or even an unexperienced programmer) that removing code is good and sometimes condensing two features into a simpler, more generic and versatile feature is positive both for code quality and usability; then again, from a marketting perspective, two specific features are better than one generic feature. And then you have ways in which more developers do get things done better, but only if managed correctly (aka. if the tasks are split along the right lines)

Yep, read Mythical Man Month