Agile and Waterfall: Software Development Frameworks at War?
Are the Agile and Waterfall software development frameworks truly at war? And what has made each so popular in the first place?
Oh, the wonderful world of software development frameworks. With last week’s blog, we had a closer look at Scrum Agile. We’ve also brought up some core differences between Waterfall and Agile development methodologies. It’s an exciting and fun topic, so we’ve figured it deserves a bit more attention.
We’ve also decided not to follow the typical “Agile (Scrum) vs. Waterfall” debate, which tends to hold Agile as the irrefutable winner. Anyone reading into different software development methodologies has definitely seen this “old bad, new good” pattern.
However, rather than demeaning one in favor of the other, we’ll measure strengths and weaknesses to determine which use cases are suitable for each. By the end of this blog, we’ll see why both Agile and Waterfall methodologies have secured leading roles in today’s software development world.
Two Different Styles of Doing Software Development
Quick reminder here: whether we speak of Agile or Waterfall, we refer to vast development frameworks. Meaning they are broad layouts presenting plenty of subsets and extensive uses. For instance, Scrum and Kanban are two well-known subtypes of Agile development. In fact, some of these subsets intertwine and draw from one another, so it’s pretty hard to trace a clear-cut picture here.
Yes, Agile and Waterfall development are different – but not exactly complimentary. Before we get to that, let’s look at the core values making up each framework.
Waterfall Software Development
The oh-so-old and outdated Waterfall method. It used to be the prevailing framework in software development, and its conceptual history goes back to the seventies.
As hinted by its very name, Waterfall is a sequential, top-down design process. This means that it breaks down development activities into successive phases. Each phase follows the previous one. In the classical Waterfall model, there are six such phases:
1. System/Software Requirements (also known as “Requirements Gathering”)
2. Requirements Analysis
2. Design (Software Architecture)
3. Development (Coding)
4. Verification (Testing)
5. Deployment (and its subsequent operations, such as migration, support, and maintenance)
An aspect essential to Waterfall development is that each phase heavily relies on the previous one. They never overlap. For instance, you can’t start designing complex software unless you’ve already gathered and analyzed its requirements.
STRENGTHS
Reliability and full functionality are core values in this style of software development.
Generally, Waterfall truly shines in large-scale projects, where the aim is to “get it right” on the very first try. So, when you’re putting out a piece of software at the end of a Waterfall cycle, it has to be fully operational, usable, and reliable.
Since the accent falls of quality and completeness, Waterfall is the firm winner when it comes to developing complex solutions – something like a bank or healthcare application. With Waterfall development, the assumption is that all the requirements traced out initially have been accounted for with great care and attention to detail.
Let’s look at another example. Imagine that your team must develop complex software for government purposes – a product that is reliable, highly secure, and ready to respond to typical challenges. Users shouldn’t stumble into any (serious) bugs after its deployment, as the functionality and reliability of your solution are vital to the institution.
All in all, waterfall development is about predictability: cost, size, requirements, possible issues – all of them must be defined and addressed in advance. If your aim is not to do the job quickly but to do it thoroughly, then Waterfall is, most likely, the answer.
WEAKNESSES
When we think of software development frameworks, Waterfall is the traditional way of doing things. As we have seen, it requires extensive research and detailed planning way in advance.
Perhaps the greatest weakness of Waterfall development is its rigidity. It doesn’t account for requirements that change in the middle of the development cycle. Teams follow processes outlined in the initial phases, making it much harder to respond to evolving market needs or unforeseen situations. This is why you wouldn’t use Waterfall development for software that has to compete with other solutions in a dynamic, evolving market. Such circumstances call for something more…agile!
Agile Software Development
We can divide the Agile development process into the so-called sprints, which are continuous iterations (repetitions) of concurrent development phases. The feedback given at the end of each iteration (development cycle) is the driving force behind the next one. Thus, iterations continue until the product is finally deemed suitable for deployment.
Basically, Agile also includes the traditional Waterfall phases we’ve just seen (or other variations), but they go in a cycle rather than follow one another in a line. Besides, these phases can be repeated, take place in any order, and even happen simultaneously – it all depends on the needs, goals, and circumstances at hand.
Agile methodologies also value continuous collaboration between development teams and stakeholders. Frequent feedback loops (typically after each sprint) ensure that the product adapts to evolving requirements or unexpected issues, which can be quickly incorporated or addressed due to the flexible nature of iterative development.
STRENGTHS
We’ve already named the most important one. Among all the software development frameworks we use today, people love Agile for its fluidity. Agile teams perform changes and iterations if and when needed instead of strictly abiding by a previously established plan.
Another one of its core strengths comes with cross-functional, self-organizing development teams. People following an Agile framework can figure out how to approach tasks without too much supervision. It’s true that Scrum, which is a subset of Agile, relies on the Scrum Master. But the latter is there to guide, help out and synchronize efforts, rather than fully manage and organize every little thing that’s going on.
Finally, Agile combines high usability with market adaptability. These dynamic teams working with dynamic processes aim to deliver workable (not perfect!) software in a fairly short time. Thus, frequent changes are made on top of evolving business and market needs.
So Agile methods work really well when you’re developing, let’s say, an eCommerce platform (a web store) for a business that isn’t quite sure about what it wants yet. Perhaps the client gives you an idea of some core features and uses cases in the beginning but discovers it needs some other ones when development is underway. Luckily, Agile can quickly incorporate these growing requirements.
WEAKNESSES
Scrum aims for small product releases which build on top of one another. But this is that it’s simply not a feasible option for large-scale, complex solutions with a fixed budget – and this is exactly where Waterfall development excels instead.
Less predictability is another common issue: if your client changes their mind too often, you might waste resources and end up off-track. Also, because Agile frameworks rely on frequent feedback loops, they demand more customer engagement. Unfortunately, managing customer communication and building software documentation from their feedback (verbal more often than not) can be pretty difficult. At times, you have to deal with delays or unresponsiveness, which can really hinder the “agility” of it all.
What’s more, the workflow specific to Agile is not exactly easy to follow. Just consider the following: maintaining constant coordination between team members, product owners, and other stakeholders; managing changing requirements; devising a cross-functional team capable of making decisions by itself. All of these aspects rely on expensive experience and professionalism from your product development team.
Agile & Waterfall: Can They Function Together?
We’ve summed up some focus points in Agile and Waterfall development in the picture above. When we place these software development frameworks next to one another in this manner, they can seem pretty different. But are they really? What if we told you there is an Agile-Waterfall hybrid methodology out there in the wild software development world?
This seemingly odd combination aims to incorporate the best of both worlds. And there are many ways to go about it. For instance, you can use Waterfall techniques to develop the clearly understood, predictive elements of your product, whereas Agile can come in handy for the more uncertain features. Moreover, your organization can simply opt for both of these methodologies, especially if it’s in the course of transition from Waterfall to Agile. In this case, use a plan-driven Waterfall framework for low-risk projects. And keep Agile techniques to iterate on activities in higher-risk projects until you achieve a desirable result.
It seems there is hope for the war between predictability and adaptability to end in peace, as long as we learn how and when to leverage them best.
Cherry-Pick What Works
As this blog puts it so charmingly, Waterfall has been oftentimes deemed the old, outdated demon of project management, product development, and software development in particular – a dragon to be slain by young Agile. But we have seen this is way off the mark.
In reality, these two software development frameworks are highly usable in their respective contexts. And so you must choose in accordance with the size and scope of your project, the nature of your client, and the overall experience level in your organization. Or go for a hybrid, if that suits you! While purists might argue otherwise, we believe that great systems arise when you’re not afraid to venture beyond current your comfort zone.