The Traditional Waterfall Software Development Life Cycle – is it Still Relevant?
The classical waterfall software development life cycle divides the software development life cycle into phases. It is easy and simple to use yet extremely difficult to implement reflection or revision.
If you are about to start a software development project, it would be critical that you know about typical project management methodologies. Naming all trusted project management methodologies, Classical Waterfall Models sit comfortably among Agile Project Management Approaches such as Scrum, Kanban, Sigma, etc. The initial application of the classical waterfall software development life cycle dated back to the 70s to manage large software development projects, and half a century later, this model is still relevant to the modern software development project. However, this model shouldn’t be used indiscriminately, project managers should carefully consider the advantages and disadvantages of the Waterfall model before applying it.
1. What is the Classic Waterfall Software Development Life Cycle?
The classical waterfall software development life cycle is the basic, simple but idealistic software development life cycle model, setting the foundation for more modern software development life cycle models. The classical waterfall software development life cycle comprises a sequential flow in which the life cycle is divided into a set of phases, in which one phase can only start after the previous phase has been completed because the output of the previous phase is the input to the next phase. As the software development life cycle models consist of sequential flow, it limits the overlap in the development process.
The approach to software development is key to the final outcomes of projects as well as the performance of the business. Although more and more developers are choosing new, agile approaches to software development, the classical waterfall software development life cycle model is still widely chosen in traditional organizational environments and processes. According to the Project Management Institute, in 2017, 51% of organizations used the waterfall approach. Toyota and Cisco are two of various brands that used this classical approach. Despite being very structured and rigid, it is still suitable for many product teams.
2. Waterfall Methodology Phases
Technically, the waterfall software development life cycle can be divided into 5 main phases, namely Requirements, Design, Implementation, Verification, and Maintenance.
- In the Requirements phase, the project manager should outline the big picture of the project with specific objectives and requirements. For example, the objective and requirements could be a B2C software that can process thousands of transactions per day with an online payment gateway or can link with a CRM system that stores millions of concurrent users. The software should be deployed in 4 months with a development budget of 10,000 USD. The clearer and more detailed the project is, the better for the project team to successfully implement the project as obscure statements could be implemented in many ways which devastate the final results of the project.
- In the Design phase, the project manager and team members discuss how to come up with ways to design solutions that meet the project’s requirements which were identified in previous phases. For example, if the requirement is processing thousands of transactions per day, the project team should consider employing highly-function servers or multiple servers instead of a single backend server because one might not be resilient. With multiple backend servers, if one goes, the system can connect with other servers to ensure smooth transaction of thousands of transactions a day.”
- In the Implementation phase, the project team selects the design layout, graphics, and technology to implement the designed solutions. In this phase, the project team also collects data and inspects whether the design is able to support the identified requirements.
- In the Verification phase, the project team tests all the implementations in phase four to determine whether it validates the initial requirements. If, for example, the initial requirement was to connect with a CRM to store millions of databases, the project team must test whether this is possible. If the system fails to connect with CRM, or the database fails to store on the system, the project team must go back and test where issues could have come up, and what are the potential solutions.
- The Maintenance phase is critical for the operation of the system. Once the system has gone through validation and verification, it still needs to be maintained, updated, and upgraded. The essential activities involve patching, upgrading, or testing for errors and fixing them if they do occur.
Each of the above phases is essential to the build of the software and must be carefully implemented to ensure the success of the project.
3. Advantages of the Classical Waterfall Model
Being the foundation for other software development life cycle models, here are the major advantages of the classical waterfall software development life cycle.
- The model is very simple, easy to understand, and use even for new developers.
- Each phase is processed at a time that limits the possibility of overlap and overload. Each phase in the model has been clearly defined with guidelines, milestones, and requirements.
- Process, activities, and requirements are very well-documented in each phase to reinforce good practices
- This model is suitable for projects where requirements can be well-defined at the start of the project and all project members share a common understanding of the project objectives and direction.
4. Drawbacks of the Classical Waterfall Model
Despite the advantages, the classical waterfall software development life cycle possesses various shortcomings, let’s discuss this in detail.
- There is no feedback path in this classical approach as it assumes that no error is ever committed by developers, or any upgrading should be made during any phase as the overall requirements have been clearly identified first-hand. Therefore, there is no room established for feedback and error correction which is a big flaw of this approach, especially for big projects that must develop in a long-time frame.
- It is almost impossible to accommodate change requests. Once again, with the assumption that all customers’ needs and requirements have been defined at the start of the project, there is no need to change throughout the project. Nevertheless, in reality, customers’ demands change constantly over time.
- The possibility of overlapping phases. Theoretically, a new phase can start only when the previous phase has been completed; however, in practice, this can hardly be maintained due to the need to speed up the time of deployment and reduce cost, phases may overlap.
To overcome these drawbacks, another approach has been developed to increase the efficiency of the software development process, read more about Agile approach to software development.
5. Final Thoughts
When developing software, choosing the right method is critical. In case you decide to apply the classical waterfall approach, you must clearly identify the deliverables of each phase. If deliverables are straightforward and testable, the waterfall software development life cycle will yield the best results.
Newwave Solutions is a trusted partner in software development projects. Despite the approach you choose, our team of experts can give you the best possible advice to increase your project’s efficiency and overall performance. Contact our consultants to discuss in detail your project today.
I am To Quang Duy, CEO of Newwave Solutions. I have over ten years of expertise providing software solutions and consulting services to significant enterprises in Vietnam and Japan, in the fields of real estate, healthcare, insurance, education, and others. The expertise I provide will be of great use to your company's growth.