The Waterfall Methodology is called this way because it develops systematically from one stage to another in a downward direction. Basically, you cannot proceed to the next stage unless you have completed the previous one first.
First introduced by Dr. Winston W. Royce in an article published in 1970, the Waterfall methodology is a classic model used in project management and project life cycle development to create a system with a linear and sequential approach.
This model is divided into several phases and the output of one stage is used as input for the following one.
In short, each stage must be completed before the start of the next one and there is no overlapping.
Although the popularity of the waterfall model has decreased in recent years towards more agile methodologies, the logical nature of the sequential process used in this methodology cannot be denied. Let’s have a thorough look.
The five stages of the Waterfall Methodology
Building a “waterfall model”, for a new project, is a rather simple process, thanks in large part to the step-by-step nature of the method itself.
Clearly there may be small differences from one project to another, but regardless of these, the basic concepts regarding what it takes to start a model are the same and can be applied anywhere.
1. Requirement analysis: During this initial stage, potential project requirements are methodically examined and documented. This paper will serve as the baseline for all future developments. This stage also often includes a feasibility study to see if the project is really worthwhile.
2. Planning: In this stage it is determined how the project will be conducted and will then be divided into various modules/activities.
3. Development: In this stage the project is actually executed.
4. Test: During this stage, tests are performed to identify and report any output problems that need to be solved.
5. Release: at this stage the output is ready to be rolled out and distributed in the market.
Waterfall methodology pros
Although in recent years the Waterfall methodology has been slowly discarded for more agile methods, it should not be ignored that this method can still offer a number of advantages. Notably, larger projects and organizations that require strict phases and deadlines could benefit from its application.
Here are the main pros of the Waterfall Methodology:
• Fits mobile teams: the use of this method allows the project as a whole to keep a more detailed and solid design scope and structure thanks to all the initial planning stages of the project and of documentation. This is especially convenient for large teams that could have employees coming and going during the life cycle of the project.
• Allows a structured organization of resources: Whilst some might argue that this is a burden rather than an benefit, the Waterfall model forces the project, and even the organization that uses it, to be extremely disciplined in its structure. Most major projects will necessarily include detailed procedures to manage every aspect of the project.
• Allows early design changes: Although it may be difficult to make design changes later in the process, the waterfall methodology is well suitable for early life cycle modifications. This is great when filling out the specification paperwork in the early stages, as changes can be made immediately and with minimal effort, since no coding or implementation has been done until then. Basically, with the Waterfall method the management of project changes is significantly smoother.
• Ideal for milestone oriented development: due to the intrinsic linear structure of a project that follows this method, the waterfall methodology is well-suited for organizations or teams that operate well in a milestone-oriented environment and fixed deadlines. Having distinct, tangible and clearly understood steps by all team members, it is fairly easy to develop a timeline for the entire process and assign milestones for each step. This does not mean that project development can be delayed, but the Waterfall methodology is particularly good for projects that have set deadlines.
Waterfall methodology cons
Here are the disadvantages of the waterfall methodology:
• Non-adaptive design limitations: Arguably the worst drawback of the waterfall model is its inherent lack of adaptability in all phases of the project life cycle. When a phase five test reveals a major flaw in system design, not only does it require a drastic leap backwards, but in some cases it can often lead to serious concerns about the legitimacy and operation of the entire system. Experienced teams and developers argue, of course, that such situations should not occur if the system was designed correctly from the start, but sometimes not all scenarios can be considered, and each project carries its own set of risks.
• It ignores customer feedback halfway through the process: Due to the strict process that this method involves, feedback from users or customers is provided late in the development cycle and this can sometimes be too little or too late.
• Delayed testing period: Whilst most modern models seek to integrate testing during development, the testing phase of the waterfall model comes relatively late in the process. This not only means that most bugs or design problems will not be discovered until the final stage of the process, but it also encourages poor coding practices as testing is just an afterthought..
A solution could therefore be to anticipate not only the normal test phase as foreseen by the waterfall methodology, but also to consider the idea of introducing an effective error management tool in the project development cycle.
To do so, a good project management software that includes an error monitoring feature can be the optimal solution.
Although it has its drawbacks, as mentioned above, a project management plan that follows the Waterfall methodology is very effective in situations where you work in a familiar scenario with various known factors and scenarios, and where the client knows exactly what they want from the beginning.