
The Waterfall model is one of the oldest and most traditional methodologies used in software development. It’s a sequential, linear approach, where progress flows in one direction—like a waterfall—down through several distinct phases. Each phase must be completed before the next one begins, and there’s little to no overlapping between the phases.
Sequential Process: The development process is divided into a series of well-defined phases, with each phase building on the previous one. The next phase cannot start until the previous phase is fully completed.
Rigid Structure: Once you complete a phase, going back to revise or change something is difficult and often costly. This makes the Waterfall model rigid, as each step depends heavily on the completion of the previous one.
Clear Documentation: Each phase results in detailed documentation, ensuring that the system is thoroughly defined at every stage. This documentation is vital for future reference, debugging, and scalability.
Phases Are Completed Once: Each phase is revisited only if needed after the final system is deployed. It’s not common to go back to earlier phases unless major errors or revisions are required.
Simple and Easy to Understand:
Well-Defined Phases:
Clear Documentation:
Predictable Timeline:
Focus on Requirements:
Inflexible to Changes:
Late Testing:
Assumes Stable Requirements:
Risk of Project Failure:
Not Ideal for Complex Projects:
The Waterfall model is best suited for situations where: