![What Is Waterfall Methodology? Here’s How It Can Help Your Project Management Strategy What Is Waterfall Methodology? Here’s How It Can Help Your Project Management Strategy](https://trangangolf.storage.googleapis.com/wp-content/uploads/2023/12/23150242/412962084_779100577563268_3371857793184435682_n.jpg)
Waterfall methodology is a widely used project management method with a linear approach. In Waterfall, each stage of the workflow needs to be completed before moving on to the next step. While there are various types of project management methodologies, Waterfall is well suited for projects where the objectives are clearly outlined from the beginning. This article covers how Waterfall works, what projects the methodology is best suited for and how it compares with Agile, another project management method.
Waterfall Methodology Definition
The Waterfall approach was established in 1970 by Winston w. Royce. It contains five phases of management, where each requires a deliverable from the previous phase to proceed. Waterfall is ideal for projects like software development, where the end result is clearly established before starting, and is best suited for projects that require a lot of predictability.
Waterfall Methodology Phases
There are five phases of the Waterfall methodology: Requirements, Design, Implementation, Verification and Maintenance. Below, we discuss each phase and the purpose for each one.
- Requirements. During this phase, you outline the big picture of your project’s requirements. These are, “high-level statements that could be implemented in many different ways,” according to Dr. Chris Mattmann, Chief Technology and Innovation Officer (CTIO) at NASA Jet Propulsion Laboratory. For example, a requirement could be that a B2B software process a million transactions per day, or serve a community of 10,000 concurrent users.
- Design. Once you understand the project requirements, the next step is to come up with ways to design solutions that meet them. For example, if the requirement is processing one million users per day, you’d consider possibilities that will best support this during the design phase. As Mattmann explained, “We probably shouldn’t have a single backend server because that’s not resilient. So maybe our design says we should have redundancy with multiple backend servers so that if one goes, we can still meet that goal of processing a million transactions a day.”
- Implementation. During this phase, you select one of your candidate designs and use technology to implement them. This could involve collecting data and inspecting whether the design is able to support the requirements.
- Verification. During this phase, you take the implementation you created in phase four and test whether it validates your requirements. If, for example, the original requirement was to process one million transactions per day, you would test whether this is possible. If you run into issues—say you can only run 500,000 transactions per day—here’s where you would go back and test where issues could have come up, Mattmann explained.
- Maintenance. The project isn’t over once it has gone through validation and verification. The system still needs to be maintained. During maintenance, you are “designing strategies for updating and upgrading,” Mattmann said. This involves patching systems, upgrading the systems, implementing a software upgrade or testing for errors and fixing them if they do occur.
Waterfall Methodology: Advantages and Disadvantages
One of the advantages of Waterfall is that it has a fixed timeline and budget because the project goals are specific and delineated from the start. Once the goal of the project is established, the Waterfall methodology does not involve frequent feedback or collaboration from the client, apart from established milestones or deliverables for each phase. This makes it easier for project managers to plan and communicate with stakeholders or business partners. However, while this can help with planning, it is also only practical when a client has a clear and fixed end goal and does not need to be involved in the process of the project’s development.
One of the disadvantages of this methodology is that addressing unexpected problems can be difficult and timely. “As you proceed from phase to phase, the phases could inform one another,” Mattmann explained. For example, challenges in the implementation phase could indicate that you had a poor design. The trouble is, “you might not ever figure that out until you implement or do verification and validation.” In these situations, the rigidity of completing one phase fully before moving on to the next can prolong project timelines. The best way to prevent this when you’re using Waterfall is to get as much information as possible to avoid the risk of needing to go back on a phase, Mattmann advised.
Use-Case Scenarios
Waterfall methodology is often used when there is a high level of reliability needed for the project. Waterfall is common for projects that, “require intense human review because the possibility that you got it wrong could lead eventually to loss of life,” Mattmann explained. The Department of Defense and the aerospace industry are two examples.
Waterfall vs. Agile Methodologies
Waterfall and Agile are two project management methods best suited for different types of projects. The Agile method was developed after Waterfall to work more quickly and better prepare for changes in software development. While Waterfall is fixed and more rigid, the Agile method is adaptable and is better suited for a client-facing work process. In the Agile methodology, the team works on multiple phases of a project simultaneously and for short periods of time.
The Agile method follows the same or similar project phases discussed above, but these could be happening simultaneously and don’t need to follow a particular order. One potential downside of the Agile method is that your team could end up doing a lot of unnecessary work. For example, one part of the team might be working on validating a prototype design that later proves to be unnecessary during the implementation process.