Your approach works when you are around to accomodate changes easily. With more red tape in the process (worst case, code developed externally), the incentives

Your approach works when you are around to accomodate changes easily. With more red tape in the process (worst case, code developed externally), the incentives to overengineer the the initial solution grow. As you point out, this is bad. But that's how I see things play out.