Which project management model is characterized by a linear sequential design process?

The Waterfall Model is characterized by a linear sequential design process, where each phase of the project flows downward into the next, resembling a waterfall. This model consists of distinct stages such as requirements gathering, design, implementation, testing, deployment, and maintenance. Each stage must be completed before the next one begins, and there is typically no return to a previous stage once it's finished. This structure allows for thorough documentation and a clear timeline but can be inflexible, as changes during later stages can be challenging and costly.

In contrast, other models like Agile, Spiral, and Iterative introduce more flexibility and repetition within their processes. The Agile Model emphasizes iterative progress and adaptive planning, allowing for changes throughout the development process. The Spiral Model combines iterative and incremental approaches, focusing on risk assessment and prototyping. The Iterative Model involves repeated cycles or iterations of development, making it easier to refine and improve upon the work. However, these approaches do not adhere to the strictly linear process that defines the Waterfall Model.