Agile vs. Waterfall: Which methodology is right for your team?

In the past twenty years, Agile has established itself as the pinnacle of project management. So, it’s easy for organizations to see the benefit of moving away from traditional approaches like Waterfall. The only problem: teams falling short of a full transition can accidentally blend Waterfall and Agile into Wagile.

Some teams argue that Waterfall offers pros Agile can’t. While Waterfall brings advantages to the table, disguising it behind a halfhearted Agile transition offers the worst of both worlds.

Below, we’ll explain each approach to help you make the right choice between Agile vs. Waterfall.

Table of contents:

• What is Waterfall?
• What is Agile?
• Agile vs. Waterfall comparison chart
• What is the difference between Agile and Waterfall?
• Can you combine Agile and Waterfall?
• How Pluralsight Flow can help you track and improve your software delivery process

What is Waterfall project management?

Waterfall development is a straightforward approach to project management. It’s a sequential methodology where projects follow a specific order of phases. Teams map out these stages and their goals before diving in. As a result, projects move along one step at a time. So if you want to revisit an older phase, you may have to start over.

Waterfall is over a half-century old and has inspired many other methods. In fact, the software development lifecycle draws from Waterfall’s structure:

• Gathering requirements: Understand what your product needs to do and why that’s valuable to users. Remember to document what you learn.
• Designing a solution: Study what you learned in step one and design a system or architecture that can sustain it. You may want to specify hardware and software requirements here.
• Building that solution: Create the components of your product in a linear sequence. Put them together to construct a working version.
• Testing the product: Before releasing your product, test its performance and security measures. Automation can streamline this part of the process.
• Releasing and maintaining it: Deliver your product to users and update it over time.

Waterfall pros

Waterfall offers a few distinct advantages, including:

• In-depth planning: If your devs have a project with precise requirements, Waterfall’s planning can help. By mapping what you need to build early on, your devs can focus on specific goals.
• Reliable oversight: Some large enterprises and government clients need to consider regulations. Teams can keep these concerns in mind at each stage and meet the highest compliance and security standards.
• Cost control: Unlike Agile, Waterfall projects set a clear end goal. This is easier to budget for compared to Agile’s more fluid structure.
• Less coordination needed: Because teams work independently and in a set order, Waterfall projects aren’t a juggling act. You only have to organize one team at a time, not all devs in parallel.
• Minimal confusion: Waterfall is an established methodology, so you won’t run into much confusion about how it works. This can cut training costs, too.

Waterfall cons

Unfortunately, Waterfall has earned a less-than-stellar reputation in recent years. It may fail on large projects with changing requirements, which is an increasing norm.

As a result, there’s a tendency to push all requested or possible changes into “phase two,” extending the project. On the other hand, devs may frontload requirements and lose control over the project’s scope. Some of these issues stem from Waterfall’s:

• Inflexibility: Waterfall doesn't accommodate changes in features or stakeholder expectations. Waterfall may fall short on medium-to-large-sized projects, where the scope is bound to change during implementation.
• Lack of innovation: Waterfall suits well-defined projects with achievable goals. Innovative work, where the end goal is unknown at the start, doesn't suit this strategy.
• Reliance on underlying architecture: Waterfall needs a stable foundation to succeed. The approach can't keep up on digital projects where the underlying architecture changes.

When to apply Waterfall

Waterfall suits projects with clear goals built on existing software. Consider taking the approach when porting an existing product to a new platform. For example, Waterfall teams can port board games to a mobile app. With that in mind, Waterfall works best with predetermined timelines and constraints devs understand upfront.

When to avoid Waterfall

You'll want to avoid the Waterfall method on any projects facing changing requirements. It also isn't suited to updating products like websites or mobile phone apps. Its infrequent releases cause user frustration and allow competitors to reach customers first.

What is the main advantage of the Waterfall methodology over the Agile approach?

Waterfall project management offers more consistency and control than Agile. Instead of juggling multiple teams and tracking changes, it presents a straightforward approach. As a result, Waterfall suits:

• Small projects since they are less likely to change
• Repeatable projects since there is a known end goal
• Physical projects since the architecture is already defined

What is Agile?

Two decades back, Agile was born in response to Waterfall's limitations. Specifically, devs wanted a more flexible approach with frequent deliveries. Whereas Waterfall sets clear goals upfront, Agile gives room to adapt and change as you go. It also gives more space for stakeholder involvement.

Agile projects don’t move in a linear sequence of stages. Different teams work on their own aspects of a project at the same time. They also use more short-term dev cycles called sprints to accommodate changes in direction. This iteration works to boost productivity but requires:

• Self-directed teams
• Thorough organization across a company
• A shared understanding of Agile across teams

Agile pros

The main benefits of Agile include:

• Adaptability: Agile teams can quickly change course between sprints to accommodate project changes.
• Faster starts: Agile requires less planning before starting a project. Since requirements are subject to change, devs can begin laying the groundwork and adjust from there.
• Stakeholder support: Agile incorporates stakeholders into the dev process. Their knowledge and expertise can assist teams during production.
• Continuous deployment: Teams practicing Agile release large projects in increments. This continuous deployment means more chances to hand over deliverables, so it's compatible with approaches like DevOps and SecDevOps.
• Early problem detection: Agile teams test security and performance early in a project lifecycle. Compared to Waterfall, this helps identify issues before they grow out of control.

Agile cons

While Agile is great for innovative work, that can mean projects have no predetermined ending. This can make the project last longer than expected. That lingering status tarnishes its reputation in some circles. While some teams love the iterative approach, Agile struggles with:

• Inflexibility during sprints: While Agile is generally more flexible, changing course during a sprint poses issues. During these short dev cycles, changing priorities is difficult and expensive.
• Complex organization: Agile requires team coordination and a shared understanding of Agile terms and workflows. Potential overlap of work and high training costs may come with this approach.
• Higher overhead: Agile requires daily meetings and recurring half-to-full-day planning sessions. Additionally, Agile can't set clear timelines and costs upfront. As a result, budgets may spin out of control.
• Transition problems: Many teams moving to Agile get stuck in their Waterfall habits. These incompatible approaches create a hybrid called “Wagile.”

When to apply Agile

You should consider Agile project management when facing projects with stakeholder involvement or changing requirements. Its continuous delivery model also suits DevOps or SecDevOps teams with incremental releases.

Finally, consider Agile when you’re developing anything with a social media feature, since user feedback is critical to the direction of the product. Ignoring this feedback can backfire quickly.

When to avoid Agile

Agile won’t always meet your needs, especially when government regulations dictate your scope and timeline. This often occurs in regulated fields like the healthcare industry. The “move fast and break things” method just doesn’t play as well in regulated fields.

What is the main advantage of the Agile approach over the Waterfall methodology?

Compared to the Waterfall method, Agile affords a more fluid take on development. Teams can adjust to changing requirements, work in parallel, and collaborate with stakeholders. As a result, Agile is good for:

• Medium-to-large-sized projects where the scope is bound to change
• Innovative projects where the end goal is unknown at the beginning of development
• Digital projects where the underlying architecture stays in flux during development
  

What is the difference between Agile and Waterfall

Now that we’ve broken down both approaches, we can compare Agile and Waterfall directly. Here are the main differences between Waterfall and Agile to keep in mind:

Development approach

Agile and Waterfall build products with different approaches:

• Agile involves continuous development to deliver the best product. By taking stakeholder input, products gradually improve over each sprint.
• Waterfall takes a more rigid, goal-oriented approach. Teams set deadlines and requirements early and deliver their product by that due date.

Project timelines

Your dev timelines will vary depending on your method. Agile bases projects on short, one-to-four-week sprints. Sprint planning occurs on the front end of a project and preps devs before they jump in. This approach offers flexibility and extensions for continuous improvement. By contrast, Waterfall operates within a defined start and end date.

Requirements

Each approach comes with requirements needed for development:

• Agile requires iteration and collaboration between teams to build the best product. Stakeholder input also shapes changing requirements.
• Waterfall needs to follow goal-oriented development based on feature requirements. Devs need to understand the full scope before starting.

Budget setting

Over a project lifecycle, Agile budgets are subject to change. As new product requirements and feedback arrive, devs can increase their budget to accommodate the change. On the other hand, Waterfall development sets a budget before each project, so devs must ensure they have the resources they need upfront.

Client participation

While Agile and Waterfall both accept client participation, they work through unique avenues:

• Agile keeps clients involved every step of the way. By continuously taking feedback, the project can meet changing expectations.
• Waterfall teams reach out to clients at specified check-ins and when offering deliverables.

Flexibility

Agile tends to offer more flexibility than Waterfall because Agile incorporates flexibility into its core structure. Sprints allow for adaptation and change across a project lifecycle. Waterfall involves rigorous planning and moving through predetermined steps on each project.

Organizational preferences

Depending on your organization structure, one approach may work better than the other. In general, Agile suits:

• Startups
• Small teams
• SaaS companies
• Enterprises with interconnected teams

On the other hand, Waterfall works better for:

• Banks
• Government offices
• Insurance companies
• Large companies with independent teams

Implementation framework

Agile and Waterfall represent broad development approaches. As a result, teams can hone their core principles into specific frameworks. Depending on your team size and goals, certain Agile or Waterfall frameworks may suit you better.

Agile frameworks include:

• Scrum
• Kanban
• Lean
• XP
• Crystal
• FDD
• DSDM

Here are some popular Waterfall frameworks:

• AgileFall
• Sashimi
• Incremental Waterfall
• Wagile

Can you combine Agile and Waterfall?

Some teams combine Waterfall and Agile to create a hybrid commonly known as Agilefall, scrum-fall, FRagile, and—our favorite—Wagile. In other cases, teams stumble into it when transitioning from Waterfall to Agile. While it can sound like a great match on paper, Wagile is built on incompatible parts.

The pros and cons of Wagile

Many leaders and teams create their Wagile process with the intent to capitalize on:

• The best of both worlds: Waterfall suits small, repeatable projects, while Agile works for medium-to-large-sized innovative projects. The hypothetical scope of Wagile would include most projects.
• Less disruption: A hybrid approach like Wagile would not force extreme change on the team. Both Agile and Waterfall devs could transition easily.
• Meeting “special” needs of an organization: Every organization has specific needs no single approach can meet. As such, some businesses assume a hybrid approach will help them meet these needs.

Wagile may promise all of this and more, but it can’t deliver. In fact, Wagile can be detrimental to your goals. It offers:

• The worst of both worlds: Wagile is intrusive for business partners and allows for a lot of scope creep, causing projects to never end.
• Confusion: Wagile demotivates early Agile adopters and firm believers when Agile rules get ignored.
• High overhead: Management often wants to keep Waterfall weekly meetings and add Agile planning sessions, daily stand-ups, and retrospectives. Altogether, this creates higher costs than Agile or Waterfall alone.

We’ll cut straight to the chase: There are no pros to Wagile. The approach promises devs a perfect method Wagile can’t provide. Fundamentally, Agile and Waterfall aren’t compatible enough to form a hybrid process. Seriously, Wagile is the worst.

When should you avoid Wagile?

Always, or when you want to succeed. Instead, commit to one methodology and leverage its strengths. That will help your organization more than Wagile ever could.

That said, you might stumble into Wagile by accident. You could find yourself using it at the beginning of a transition from Waterfall to Agile. During this switch, people may say Agile isn't working. But when you're in a Wagile state, you're not in Agile. Agile will work just fine once you can get there.