Waterfall

Waterfall solves the problem of needing strong phase control when change is expensive or constrained. It organizes delivery as a sequence of requirements, design, implementation, testing, and release.

Where it fits

Waterfall belongs in software management and delivery methodologies. It is less common for fast-changing product software, but it can be useful where regulation, contracts, or hardware dependencies make iteration difficult.

Motivation

Some projects need formal sign-off and predictable phase gates. Waterfall makes those gates explicit.

Common mistakes

• Using Waterfall when requirements are still highly uncertain.
• Discovering integration and user feedback too late.
• Treating the plan as more real than evidence from implementation.

Related concepts

• Agile
• Acceptance Criteria
• Roadmap