Earlier quoted context omitted.
Agilistas like to pretend that if you're doing waterfall you can't ever go back to the previous step. Whereas in practice, if you find something wrong or confusing with the specification, you just hunt down the business analysts and ask them what drugs they were on when they pooped out the spec. And then after walking them through their mistake, you get a new and better spec. If you do it often enough, they will star…
"Agilistas like to pretend that if you're doing waterfall you can't ever go back to the previous step." The Agilistas are correct. The reason for this is that Waterfall was constructed deliberately as a strawman . The very point of constructing Waterfall was to draw a distinction between the process as it was being presented to the VP, or in this case as it is presented to the customer, and the fact that in practice…
For example, large-scale construction projects like skyscrapers are run by gantt charts and committees, which sounds unbelievable and like a disaster waiting to happen. It's like the opposite of every startup I've worked at in the last 4 years. Except it actually works and they keep the everything running smoothly through:
* (at the top level) real time adjustments to huge room-filling charts that shown all the dependencies.
* (at the grunt level in the trenches) an abundant use of checklists to keep work mistake-free and to avoid groups stepping on each other.
* (at all levels) constant and real time communication. Lots of it.
So yeah, I think it's hard to write off waterfall as both ineffective and non-existent if a large industry uses it to such a degree.