The Waterfall method has been predominant in the software industry since the '70s. It's proved so long lasting because it provides the required outcomes to customers and teaches discipline in completing work in the stipulated time frame and under the agreed upon budget. Right up until the time of release, however, there are changing market trends and the client's needs for the application under development are regularly updated. To overcome this delay, the client needs early development interaction with the service providers. Hence, Agile came into the picture, which accounts for changing market trends through flexible, short development Sprints. So, the big question is, which one is best?
Pros of Waterfall: The Waterfall methodology is very good when the project has a tight schedule, tight budget, and fixed timelines with fixed outcomes. Because of this, the importance of Waterfall cannot be overlooked completely for future projects. It helps improve the quality of the product with its progress gate system, where it is not possible to proceed to the next stage of the project without completing the previous one. It also requires teams to define the potential factors or risks of project failure in the early stages of development, which can help save on some of the cost involved in future maintenance. It also focuses on documentation for future use which helps new team members get familiar with the software and get up to speed faster.
Cons of Waterfall: In my opinion, the Waterfall model is criticized in the market too much these days. With that said, however, are there some definite disadvantages. Firstly, it asks for fixed requirements which are not allowed to be changed during the course of the project. And, if mandatory, separate change requests need to be raised, which only drives up the cost of development. The requirements for the project are made on early assumptions, which may be proved incorrect as the project progresses. Also, it divides teams into separate entities of designers, programmers, and testers. Do these critical points clearly overshadow the advantages of the Waterfall model? If yes, what is the solution?
Pros of Agile: The Waterfall model inspired the development of the Agile method. Agile helps teams deal with unpredictable challenges. A team working in Agile has complete authority to change its approach to reach the desired output. Also, the various steps of the development cycle work in parallel in Agile, i.e., all the stages are running simultaneously to accommodate any changes or updates in the requirements. Big IT giants like Google have moved from Waterfall to Agile due to its flexibility and adaptability. Agile helps in incremental and iterative growth of a project with continuous feedback for improvement.
Cons of Agile: Like Waterfall, Agile methods, too, have a few pitfalls which keep teams from going Agile. A tendency toward a lack of documentation increases dependencies on a few team members. The project will fail if the client does not provide insight into the requirements regularly and clearly. Only experienced team members are capable of coping with the demanding needs of the Agile method and are capable of making development decisions.
Conclusion: When starting a project, potential risks, errors, advantages, and disadvantages should be considered to make it easier to decide between using Waterfall or Agile. Keep budgeting in mind, along with possible risks and documentation when deciding. We can also follow a hybrid (collaborative) approach which contains aspects of both Waterfall and Agile. In a hybrid approach, high-level requirements and designs are created and developed in an Agile way using Sprints.