Waterfall Methodology – The Most Successful Development Model

This article helps you clearly understand the Waterfall Methodology which has been the most successful software development model over the years.

The Waterfall model is a step-by-step approach for carrying out the design and development of a software product. Since the lifecycle of this method resembles with a water stream flowing in a river, hence it took the name as the Waterfall methodology.

In the waterfall process, the progress of a project moves ahead sequentially. One stage finishes and the next one starts. None of the phases overlap each other. It guarantees the success of the waterfall model when the projects are small with clear requirements and a fewer no. of unknowns.

The waterfall model came into the light during the late 1970s when Winston Royce used it to reduce the high cost incurred in releasing new revisions of a product. With the waterfall approach, he was successful in delivering quicker at a lower price and with fewer efforts. In this model, the first stage focuses on freezing the requirements, the next one gets the design finalized, and after that, the actual development begins.

Waterfall Methodology Lifecycle

The waterfall model life cycle consists of the following six stages:

Waterfall Methodology

Waterfall Methodology

1. Requirements:

In this stage, the emphasis is on collecting the expectations and goals of the project. The risk assessment also happens alongside.

2. Design:

Once there is agreement on the requirements of the project, the team can begin work on finalizing the core structure of the product.

The architects who are senior members of the team study the requirements and prepare a blueprint for the programmers to work on a schedule for meeting the goals.

3. Building:

Here, primarily the development/coding/implementation takes place. The developers also perform the unit testing of the modules.

4. Validation:

In this phase, the product goes through stress testing, the testers hunt for bugs and ensure that the software fulfills the customer’s requirements.

5. Packaging and Installation:

Once the testing team certifies the products through validation, the product gets packaged as per the agreement signed. After this, an additional cycle of testing and validation takes place.

6. Maintenance:

The software enters into the maintenance stage after releasing to the customer. This phase runs based on the agreement where the client gets continuous support and expect bug fixes if encountered.

Advantages of the Waterfall Methodology

The waterfall primarily recommends to invest the bulk of the time, capital and energy up front: 20-40% in the first two stages, 30-40% on the development/coding, and the remaining spend on the implementation and maintenance.

  • It is useful for projects which give more priority to quality than to the cost or the time duration.
  • Suitable for projects which are easy to implement and doesn’t need a lot of resources and efforts.
  • The stability of the model makes project management easier.
  • Both the customers and project manager can actively monitor the progress at any stage of the development.
  • Since all phases occur without any overlap, hence it reduces the project complexity.
  • Flexibility in communicating with the clients, especially when any critical requirements needs a design discussion.

Disadvantages of the Waterfall Methodology

Every model has come with its limitations; hence, it may not work the same for every project. The waterfall methodology suites the best for projects when there are clear requirements and no ambiguity, size is short, and all stakeholders agree on the technology used. But it also comes with some disadvantages which are as follows:

  • Not appropriate for long duration or large-scale products.
  • Lower flexibility in the process indicates that the project may face difficulty when there are high-level changes in requirements.
  • Since the next stage is dependent on the outcome of the previous step, hence even a small change in the project scope can pose a big challenge.
  • Some of the projects won’t follow the workflow laid down by the Waterfall model. And some may even bring shocks and highlight the vulnerability of the methodology.
  • If the customer requirements are not clear or not available early, then it could create significant complications later in the project lifecycle.
  • Any modification or upgrade request for the hardware and software may have a higher impact on the development and lead to an escalation in the project timeline.
  • The Waterfall process guides to pick most of the work up front which causes the delivery of the software very late in the project lifecycle.
  • After the product gets to the validation stage, it makes it difficult to go back to the coding or the requirement phase to resolve something.

Must Read – 100 Manual Testing Interview Questions for Software Testers of All Experience Levels.