These days, most software development teams choose Agile methodology to organize their work. The Agile vs. Waterfall debate still rages, though. Many people question whether Agile works better than Waterfall in all circumstances. Does Agile deliver great ROI? Does Agile help teams work faster? Let’s take a close look at both Agile and Waterfall. We will examine the merits and drawbacks of each approach.
Waterfall methodology takes a linear path. Teams using Waterfall plan each step of the software development project in detail. Each step in the Waterfall model relies on the previous step’s completion. Organizations in manufacturing and construction first started using waterfall. It helped them to keep costs down with thorough planning. Design changes late in the manufacturing process prove prohibitively expensive. By using Waterfall, they ensured that they faced no big expensive surprises.
Waterfall made its first appearance in software development in the 1950s. Herbert D. Benington described the process in a paper presented at the Symposium on Advanced Programming Methods for Digital Computers on June 29, 1956. The term Waterfall did not appear until 1970. Winston W. Royce diagrammed a process known as the “waterfall model.” Royce laid out five steps to add to Benington’s process. He had concerns that the lack of testing during the development process could cause trouble for the teams.
Waterfall begins with the team gathering and documenting requirements. During this process the Customers and Stakeholders have input. Next, the developers design the solution that meets the requirements. Next, they write the code and test. Finally, the team fixes any errors or bugs and delivers the finished project to the Customer. Each of these steps stands alone. The software development team must not jump ahead. They must finish each step before beginning the next.
Advantages of Waterfall Methodology
- Waterfall offers extensive documentation
- All steps in the project have detailed documentation to eliminate misunderstandings
- Teams know the scope of work because of thorough requirements gathering
- Customers involvement not necessary during the project, only at the beginning and end
- Great for managing dependencies
Disadvantages of Waterfall Methodology
- Ineffective if requirements gathering has flaws or gaps
- Testing only happens at the end of the project, bugs may prove expensive to fix
- Customer expectations may shift during development
- Difficult to revisit a complete step
Agile Development came about as a response to teams feeling slow and constrained by Waterfall. Waterfall methodology, while simple, is highly regimented. Developers wanted a more nimble, user-focused model. They wanted to make changes and create software that met stakeholder requirements quickly and precisely.
Agile development focuses on the needs of the customer and end-users. The development cycle is a transparent process. The process fosters stakeholder involvement and participation at every step.
The Agile method is different from traditional team organization. Where a traditional team may have several projects at once, an agile team focuses on one project at a time. They give all their attention to a single goal. Agile team members do not have rigid job roles and titles. Instead, the team members are valued for their skills and contributions to the project.
Agile and Scrum
Agile development works as an iterative process. The software develops incrementally rather than as a big package as in Waterfall. Many teams use a special type of Agile process known as Scrum. Scrum works as a framework using Agile principles. Scrum uses Scrum Teams and Scrum Masters to develop their project. Each Team organizes their work using User Stories and Sprints. Daily Standup Meetings help the team focus and communicate. Agile works more as a philosophy. Scrum is how that philosophy works out in the real world.
Advantages of Agile Methodology
- A customer-focused approach, User Stories mean the team works on what matters for end-users
- Self-organized team work collaboratively
- Continual testing during the process finds bugs and problems early
- An incremental approach keeps Stakeholders involved in the whole development cycle
- Less time spent documenting, more time implementing
Read more in Advantages of Agile development article.
Disadvantages of Agile Methodology
- Customers might have time or desire for involvement
- Teams must avoid scope creep and adding extra work to Sprints
- Not as simple or predictable as Waterfall
Both Agile and Waterfall work well as project management systems. They differ in important ways. These differences help teams decide which method will work best for their project. Agile is incremental and iterative. Waterfall works sequentially. Agile Scrum uses Sprints for organizing projects. Waterfall uses project Phases. Agile focuses on customer needs. Waterfall just focuses on finishing the project. Agile teams can work without a project manager, Waterfall teams require a project manager.
Differences between Waterfall and Agile Methodologies
|Breaks projects into Phases||Uses Sprints to organize projects|
|Complete project delivered at the end of development||Incremental approach, teams deliver work as they complete it|
|Sequential and linear||Incremental and iterative|
|Highly structured||Flexible (and Agile!)|
|Change not possible after the start of the project||Changes allowed throughout planning, teams can put changes in future Sprints|
|Testing only at the end||Testing throughout|
|Works well for projects with strong and easy-to-understand requirements||Allows for flexibility and change of requirements|
|Extensive requirements gathering limits risk||Risk mitigated by testing and Sprint Retrospective meetings|
Which one is better for your project?
Waterfall works well for teams that do not have a customer available to provide feedback and support. If they only have the voice of the customer available in a limited amount, Waterfall can work. Waterfall also works well for small, well-defined projects. Agile functions well for complex and large projects. Agile allows for flexibility and change. Agile has an unstructured approach. Waterfall has a rigid structure. Using the Scrum framework, Agile projects move faster than Waterfall projects. So as you can see, Agile tackles projects with unknowns and complexity. Waterfall favors simple, small and well-defined projects.
Here at Blocshop, we harness the power of Agile and Scrum. We organize our teams to deliver the best of what they offer. We complete our projects on time and under budget. If you would like to learn more, please do get in touch.