Waterfall Methodology

Waterfall is a linear, sequential project methodology where work progresses through defined phases—typically requirements, design, implementation, testing, and delivery—with each phase completing before the next begins. Unlike agile's iterative approach, waterfall assumes you can define requirements upfront and execute in a predetermined sequence. It's called "waterfall" because progress flows downward through phases like a waterfall, with limited ability to go back once you've "fallen" to the next phase. Waterfall works well in specific contexts. When requirements are clear and stable, when the client needs a fixed deliverable with predictable scope, when regulatory or compliance processes require documentation at each stage, or when the project has hard dependencies (you can't test until you've built), waterfall's structure provides clarity and predictability. Many traditional agency projects—website redesigns, branding projects, one-off campaigns—follow a waterfall-like structure even if not formally named. The typical waterfall phases include requirements gathering (discovery, specification), design (concepts, wireframes, designs), implementation (development, creation), testing (QA, review), and deployment (launch, delivery). Each phase has defined outputs and often requires client approval before proceeding. The project plan is established early and followed; change is managed through formal change control rather than continuous adaptation. Waterfall's main limitation is inflexibility. If requirements change mid-project—and they often do—waterfall struggles. The sequential nature means you might not discover issues until late in the process. And the upfront commitment can feel heavy for clients who want to "see as we go." For these reasons, many agencies use hybrid approaches—waterfall-like phases with checkpoints, but with some flexibility for feedback and adjustment. Common mistakes include using waterfall when requirements are unclear (setting up for rework), not building in change management (treating the plan as immutable), and rigid phase gates that don't allow for learning (discovering problems late). The most successful agencies match methodology to project type—waterfall or waterfall-like for fixed-scope, well-defined work; agile or iterative approaches when flexibility and adaptation are needed.