I think the point being made is that many projects start as an idea that is then brought into the prototype phase, iterated upon, and then is complete whenever

I think the point being made is that many projects start as an idea that is then brought into the prototype phase, iterated upon, and then is complete whenever the project delivers a significant increase in current capabilities compared to the current systems. This in contrast to the F-35 project which apparently decided all the capabilities up front and then has went about designing an aircraft to somehow reach all those goals. Whether or not it will is a subject of ongoing debate. It also somehow has wound up making 3 different airframes. A good example of this would be Soviet copies of the B-29 & the V-2. In both cases there was pressure to "build our own that is better". Apparently Stalin got involved in both cases and demanded that a way be found to produce a domestic copy first, then learn from that, & produce a domestic design next. Not sure how accurate that is, but it seems to have worked out. Soviet long range bombers & Soviet missile systems are certainly nothing to scoff at.