I’m getting pretty old so I have experienced multiple waterfall projects. The comic should be
You want to go to mars You spend 3 months designing a rocket You spend 6 months building a rocket You spend a month testing the rocket and notice there is a critical desing flaw.
You start over again with a new design and work on it for 2 months You spend another 6 months building it You spend 2 months testing
Rocket works fine now, but multiple other companies already have been to Mars, so no need to even go anymore.
There was a time before Windows where a lot of people used MS-DOS and it was all terminal. Maybe computers where less popular back in those days because of the learning curve, but still many people used a PC with just the terminal.