[Waterfall](https://leadinganswers.typepad.com/leading_answers/files/original_waterfall_paper_winston_royce.pdf https://leadinganswers.typepad.com/leading_answe

[Waterfall](https://leadinganswers.typepad.com/leading_answers/files/original_waterfall_paper_winston_royce.pdf https://leadinganswers.typepad.com/leading_answers/files/ori...) was an incremental design process directly in opposition to the hirearchial process that it's commonly conflated with. That's the paper that coined the term Waterfall, note the contrast between the final Waterfall process from the traditional process (figure 10). "Documentation Driven Development" is basically Royce's Waterfall under a different name. Waterfall has the following 5 requirements/steps: 1. Design first. It'll get replaced (see step 3), but is needed for requirement 2. 2. Document the design. This defines what you're building (this time around) and the tests. 3. Do it twice (build a MVP, test, refactor & replace it as requirements become clear based on customer feedback, update the design & docs & tests, use those tests for the improved version). 4. Plan, control, and monitor testing. 5. Involve the customer. Requirement 3 is what makes Waterfall inherently an incremental iterative process.