This sounds like "Broken Windows Syndrome". Once a system gets to the point where more than (somewhere between 30-50%) is connected together, developers stop c

This sounds like "Broken Windows Syndrome". Once a system gets to the point where more than (somewhere between 30-50%) is connected together, developers stop caring about keeping it modular, because it's clear to them that their efforts are a waste of energy. From that point onwards, the project becomes a cesspool of hackery.