And cost overruns and delays in the 00s and 10s! People here on HN keep telling me I'm imagining things, that Waterfall either isn't bad or isn't real. But a 9-figure project I was (fortunately briefly, though not brief enough, around 1 year) on was several years late and delivered only half the features the users needed. Why? Because they made the plan in the mid-00s, and the circumstances changed but the plan didn't. They did what Waterfall describes, they committed to their initial analysis and plan and never looked back. Fortunately they learned after that, but it was a costly exercise.