If you want to know why we're having such problems, notice that the final Capabilities Description Document (CDD) appears at the top just before Milestone B, and never feeds back into product development. Add in the "Fundamentals of System Engineering Management" ca. 2000, where System Analysis is redefined as a "management and control activity," and I think we can completely explain why 70 out of 74 major acquisition programs out of the last 10 years have been in trouble (GAO report to Congress).

If we really want to improve the process, we scrap the "V" diagram and "Fundamentals," return to the 1990s version with a traditional waterfall approach to development.