I was talking about software, not spaceships. Software, being soft, is fundamentally different. However, you should watch the Poppendieck talk I linked. The Em

I was talking about software, not spaceships. Software, being soft, is fundamentally different. However, you should watch the Poppendieck talk I linked. The Empire State Building had construction start before they finished designing it. The waterfall hallucination, where people imagine perfect results come from perfect plans perfectly executed, has been hugely enabled by software. But if we look at the actual results of heavily planned activities, like buildings, roads, and weapons development, the track record is terrible. So if modern planning techniques don't work well even in areas, like construction, that they are most suited for, then it should be no surprise that people are skeptical when they are applied to domains that are very different, like software.