Agile vs Waterfall
Much of a software development team’s performance depends on the methodology it chooses to execute a project. The two most popular approaches are Agile and Waterfall. Each has its advantages, disadvantages and use cases. This article will provide comprehensive information about each methodology to help you choose the one that best suits your needs.
Waterfall
Waterfall is a traditional approach to software development performed in stages. Team members do not begin a new stage until the previous stage has been completed and approved. This model is convenient for companies with a hierarchical structure who are unable to bring different departments together to negotiate project details.
Waterfall software development encompasses the following stages:
- The team accepts and documents client requirements that guide decision-making throughout the entire project. Beyond this stage, once developers have already moved on to software development, the client cannot change the project requirements. They can only receive and approve the end product upon completion.
- Developers draft a design that complies with client requirements.
- Units, code, systems and user acceptance are tested.
- Bug fixing is done to ensure flawless performance.
- The finished software product is presented and delivered to the client.
The Waterfall approach is most effective for small projects with transparent requirements that do not require adjustments to development logic from one stage to the next.
Advantages
Waterfall development has certain distinct advantages:
- Straightforward project organization. Developers understand what results to obtain at each stage and can easily review them.
- The development process is not interrupted to negotiate details with the client, meaning faster delivery of the finished product.
- It is easier to gauge progress by comparing the product’s current state with the clearly defined end product.
- Well-ordered documentation.
- If new participants join the team, it is easier to bring them up to speed.
- Team members do not need to dedicate all their time to the project. While the project manager negotiates requirements with a client and testers create and run scripts, developers are free to work on other projects until they are needed.
- The client does not need to hold regular meetings with the development team.
- The client receives a holistic end product that is up and running, rather than separate pieces of code that they cannot observe in action. This prevents a “piecemeal effect,” where individual elements and features are approved with the client and then added to the product, where they may fail to work as expected.
Disadvantages
Clients often find it difficult to visualize product details and fail to provide accurate specifications. This can lead to disappointment if the product does not meet the client’s expectations. Issues may arise if a client asks a software developer to add features that are not specified in initial documentation, or to remove specified features.
It can be costly for developers to change software, adding time that was not included in the original estimate. Changing a small feature in one layer can require additional changes in other layers. Clients may refuse to pay for a product that falls short of their expectations.
Accurate product specifications at the planning stage are vital for the overall success of a Waterfall project. It is recommended to use mockups and wireframes to visualize the final result and make changes early on.
Agile
Agile development is an interactive process that delivers early iterations of a product’s features and refines them in response to client feedback. Development and testing are performed at every stage of the development process. There is a loosely structured work plan where the project is divided into phases, and subdivided into sprints. Daily meetings are held to share intermediate results.
Each sprint has a deadline and objectives, agreed upon with the client. If the team fails to accomplish tasks within the sprint by the deadline, obstacles and complexities are taken into consideration when planning the next sprint. If the team attains sprint objectives, the client evaluates the current state of the project at an end-of-sprint demo and approves the team’s plan for further development.
Advantages
- As a direct participant in the development process, the client can identify mismatches at an early stage, when they are easy to fix.
- Agile methodology quickly releases a basic version of the product. It can be introduced into the client’s workflow, tested in the field, and gradually refined.
- Customer satisfaction is usually high, since Agile teams embrace the client’s aspirations and pay close attention to features that can improve the client’s business.
- Agile teams are usually highly self-organized due to the need for ongoing planning and decision-making.
- Since each sprint has time limitations, it is easy for a customer to evaluate expenses, approximate the cost of each task and set priorities.
- User stories are taken into account when deciding on the product’s properties. Instead of a set of IT elements, an Agile team creates a solution that helps a client’s business meet their customers’ needs. Beta testing can be performed after each sprint to collect user feedback and decide on further development.
- Division of a project into sprints and frequent reviews allows developers to set manageable goals and pay greater attention to details, ensuring product quality.
Disadvantages
- While some clients enjoy taking part in the creation of their application or website, others want to receive ready-made solutions with minimal involvement. For them, Waterfall is definitely a better option.
- Full dedication and constant participation in the project are required from developers. This may pose a problem if the software development company has multiple projects lined up with rigid deadlines.
- Due to frequent changes in product requirements and deadlines, development costs may exceed the original estimate and grow beyond the client’s planned budget.
- It is easy to implement Agile methodology when all involved parties work in a shared space. The client may be unable to visit the software development company on a daily basis. Tools like Skype and Zoom can help to address this issue.
Waterfall vs Agile: Which Option is Right for You?
Neither Agile nor Waterfall provides a one-size-fits-all solution. Decision-making should be based on the unique requirements of each project, the development team’s commitment to other projects, and the client’s willingness and availability to continually be involved. Some projects are completed using a hybrid of the two methodologies. Other approaches also exist that may be more suitable for certain projects.