I get this point. But coupled with lack of expertise & experience, lack of QA and lack of dependency tree (what feature is used where), the result can be amateurish at best and catastrophic at worst. In the case of DU, it was more the latter.

Again, the cynic in me can't accept the "cheaper" argument. Apple has lack of funds to properly hire people who are not afraid to go into complex existing code? I get this argument in a start-up environment, but won't accept it in the case of the largest tech company in the world. This is just bad management.