DOD codified Royce's waterfall (which he, himself, did not name in that paper) in a set of documents on officially endorsed software acquisitions processes. The

DOD codified Royce's waterfall (which he, himself, did not name in that paper) in a set of documents on officially endorsed software acquisitions processes. There were others, but Waterfall was one of them. Its critical failing is that it's an idealized process that cannot withstand uncertainty or change, but it looks really pretty in charts so people selected it without serious thought put into it.