AppDev 101: A Comparison of Agile and Waterfall Project Methodologies

Choosing the right application development methodology will have a big impact on the success of your project. Agile and waterfall are two of the most popular approaches, and there is ongoing discussion about which is the best. A comparison of the two will help you choose the method best for your project. As you’ll see, there isn’t one answer to the question of which methodology to use. It all depends on your business and your development team capabilities.

Agile Methodology: Defined

The agile methodology was introduced in 2001 by a group of software developers who wanted better ways of developing software. It focuses on people working closely together, results reached by iterative development, and flexible responses to change.

Waterfall Methodology: Defined

The waterfall methodology is more traditional in its approach. Using the waterfall methodology, teams make concrete plans for the life of the project. The approach is linear and sequential, where each phase is reviewed and verified before a new phase is initiated. The work completed in each phase flows down to the next, which is where the term waterfall comes from.

What are the Key Differences Between Agile and Waterfall?

Both application development approaches can produce quality software. But, there are distinct differences in how the two methodologies reach that goal.

• Agile leads teams to work in increments, while waterfall is linear
• Agile teams work in sprints, while waterfall projects are divided into phases
• Agile teams produce working applications at the end of each sprint, while waterfall teams produce a complete application after the build phase
• Agile teams work on a series of small projects that come together into a whole, while waterfall teams work toward one overall outcome
• Agile’s structure is focused on satisfying the customer, while the waterfall structure focuses on completing a successful project
• Agile requirements are set daily, while waterfall defines all requirements at the start of the project
• Agile teams can easily respond to changes in requirements, while waterfall teams discourage changes after the initial requirement definition
• Agile performs testing during development, while waterfall tests at the end of the build phase

Agile Methodology: Pros and Cons

If your organization uses the agile methodology effectively, it is an excellent AppDev approach. But, there are pros and cons, and situations where it works better than others.

Pros:

• Development is quick and flexible
• Defects are identified and fixed faster than when using waterfall
• Small teams working on a variety of tasks tend to avoid slowing phases of development
• Changes can be made during development whenever needed

Cons:

• Agile requires an experienced Scrum master who is comfortable with the quick pace
• If customers aren’t willing to stay involved, they will get frustrated with the demands on their time
• Teams must be well-organized and self-governing, even though some members may be remote

Who Should Use the Agile Methodology?

You should consider several factors when choosing the agile approach. For example, agile works best when:

• you have an experienced AppDev team, or one with good support
• your business is focused on continuous improvement
• you need to respond to a rapidly changing environment
• you want your large corporation to streamline business processes and respond to changes faster
• your customers and stakeholders are educated about why their participation is required and how it benefits them, and they commit to the process

When you use the agile methodology, you’re establishing an environment where customers, stakeholders, and the project team can all play a part. When the team produces working applications at the end of a sprint, everyone involved can attend a sprint demo and see exactly how the application works. The project team can get feedback from the customer, and changes can be incorporated into the next sprint.

This iterative process helps the team to respond to requirement changes, and even the team members doing the most basic part of the project see the result of their efforts. Agile projects generally achieve higher customer satisfaction since communication is key and the team can easily manage changes. Since the team has committed to a specific deliverable for every sprint, and since everyone contributes to it, the motivation among team members stays high.

Waterfall Methodology: Pros and Cons

The waterfall methodology, like agile, has advantages and disadvantages, and situations where it works best.

Pros:

• it’s easy for teams of any size to manage the formal and ordered processes
• structured development phases provide stability for newly formed teams
• setting requirements at the start of the project reduces the complexity of the project
• planning for the entire project at the start makes it easy to manage expectations, risks, and budget

Cons:

• application development is slower and less flexible
• defects typically aren’t discovered until the testing phase, which occurs after the build phase
• it’s difficult to incorporate changes

Who Should Use the Waterfall Methodology?

• teams that work best with a predictable and sequential approach
• less experienced application development teams
• if your business doesn’t value change or taking risks
• if your customers and stakeholders aren’t or can’t participate
• if your projects are small and not complicated
• if your projects have long timeframes

When you use the waterfall methodology, you’re establishing an environment that is methodical and where there are few surprises. Project requirements are set at the beginning of the project and don’t change significantly. Roles and tasks are defined for each phase of the project and those phases are predictable in how much time they will take. It’s easy to track milestones because the project follows a pre-defined path.

It’s the best approach when customers and stakeholders don’t want to or can’t participate. However, that means that customers won’t see the application until the end of the project, which can complicate testing and delivery. Waterfall may not be the best approach for projects that will take a long time because over an extended period of time, changes will most certainly be required.

How to Choose?

Recent studies such as the Chaos Report published by Standish Group indicate that in most situations, the agile methodology is more effective. The Standish report indicated that agile projects had a 60% greater success rate than non-agile projects. They went even further by discovering that waterfall projects are three times more likely to fail.

That doesn’t mean that you should use agile in every situation. As you’ve seen through this comparison, there are valid reasons to use both approaches. But, choosing the wrong AppDev approach is only one of the things that can cause a project to fail. For more information, read our whitepaper, “4 Reasons Why Application Development Projects Fail.” With the large cost of a failed application development project, we want to help you identify the four reasons that most commonly cause projects to fail. We also provide seven solutions that you can use to overcome application development challenges.

If you’re interested in using the agile methodology, but you don’t think your team is ready to take on an agile project, Datavail has alternatives for you. Learn more about Datavail’s Application Development Sprint Teams. Our dedicated sprint teams are available on demand to scale up your development team without losing momentum. We can also provide the leadership you need to develop your own sprint teams, allowing you to use the methodology that most developers find most effective.