What are some of the challenges with the waterfall methods that prompted the software industry to come up with alternatives like agile?

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Posted by: Lucid Content Team

If you’ve researched project management methodologies before, the Waterfall methodology has probably come up. On lists of popular, trusted project management methodologies, Waterfall sits comfortably among agile, Scrum, Six Sigma, and Kanban. Dr. Winston Royce first defined the methodology in 1970 in a paper about inefficiencies in large software development projects, but no one is credited for individually creating the methodology.

Almost half a century after it was identified, Waterfall still has relevance in the modern business world—but it shouldn’t be used indiscriminately. Read on to learn more about the advantages and disadvantages of the Waterfall model and to see how Lucidchart can help you and your team apply it to your next project.

Waterfall relies on teams following a sequence of steps and never moving forward until the previous phase has been completed. This structure is suited to smaller projects with deliverables that are easy to define from the start.

Ben Aston from The Digital Project Manager explains, "Waterfall is generally regarded with some disdain as an inefficient and passé traditional project management approach. But Waterfall can be a useful and predictable approach if requirements are fixed, well documented, and clear, if the technology is understood and mature, if the project is short, and if there’s no additional value gained from 'going agile.' A Waterfall approach can actually provide more predictable end result for budget, timeline, and scope."

Here’s an in-depth look at what the Waterfall methodology does best.

1. Uses clear structure

When compared with other methodologies, Waterfall focuses most on a clear, defined set of steps. Its structure is simple—each project goes through these steps:

• Requirement gathering and documentation
• System design
• Implementation
• Testing
• Delivery/deployment
• Maintenance

Teams must complete an entire step before moving onto the next one, so if there are roadblocks to completion, they’re brought to light right away. Half-finished projects are less likely to get pushed aside, leaving teams with a more complete, polished project in the end.

In addition to being clear, the progression of Waterfall is intuitive. Unlike Six Sigma or Scrum, Waterfall does not require certifications or specific training for project managers or employees. If you visually outline the process at the beginning using Lucidchart and explain the methodology, team members will be able to jump into the Waterfall system without a steep learning curve slowing their progress.

2. Determines the end goal early

One of the defining steps of Waterfall is committing to an end product, goal, or deliverable at the beginning, and teams should avoid deviating from that commitment. For small projects where goals are clear, this step makes your team aware of the overall goal from the beginning, with less potential for getting lost in the details as the project moves forward.

Unlike Scrum, which divides projects up into individual sprints, Waterfall keeps the focus on the end goal at all times. If your team has a concrete goal with a clear end date, Waterfall will eliminate the risk of getting bogged down as you work toward that goal.

3. Transfers information well

Waterfall’s approach is highly methodical, so it should come as no surprise that the methodology emphasizes a clean transfer of information at each step. When applied in a software setting, every new step involves a new group of people, and though that might not be the case at your company, you still should aim to document information throughout a project’s lifecycle. Whether you’re passing projects off at each step or experience unexpected personnel changes, Waterfall prioritizes accessible information so new additions to the team can get up to speed quickly if needed.

You can maximize your benefits from this characteristic of Waterfall by staying organized with the right process. Use Lucidchart (it’s free to sign up!) to document processes so each team member knows what has already been done on a project when it gets to them.

The disadvantages of the Waterfall model

Waterfall is a respected methodology, but lately it’s faced criticism for being an outdated model. The methodology’s limitations become more apparent depending on the size, type, and goals of the project it’s guiding. Rather than adapting your organization to Waterfall’s guidelines later, consider these limitations to assess whether Waterfall is truly a fit for your team.

1. Makes changes difficult

Waterfall is based entirely on following a set of steps that keep teams always moving forward. The methodology, in its traditional form, leaves almost no room for unexpected changes or revisions. If your team has loyally followed the steps of Waterfall nearly to the end of the project but then faces an unplanned roadblock that necessitates a change in scope or goals, pivoting won’t be easy. You’ll have put a considerable amount of work into a project under very specific, rigid assumptions. A sudden change to the parameters of the project could render much of the work you’ve carried out up to that point useless, which can throw off the entire timeline.

If your team’s projects are unpredictable or involve frequent change, consider adapting Waterfall to allow more room for reflection and revision as you go, rather than just at the end, to prevent wasted time and energy. If you decide to go this route, tailor a Lucidchart template to your team’s version of Waterfall to keep everyone aware of how to use the adjusted process.

2. Excludes the client and/or end user

As an internal process, the Waterfall methodology focuses very little on the end user or client involved with a project. Its main purpose has always been to help internal teams move more efficiently through the phases of a project, which can work well for the software world. However, if you work in an industry other than software, clients often want to be involved during a project, adding opinions and clarifying what they want as the project moves forward.

If your projects have clear, unchanging goals from the beginning and you aren’t responsible for updating end users or clients through the development process, then Waterfall will probably work well for your team. In other cases, consider an agile methodology to better anticipate change and keep stakeholders informed through the life of the project. By involving stakeholders, you lower the risk of late requests for change throwing off your project deadlines.

3. Delays testing until after completion

Saving the testing phase until the last half of a project is risky, but Waterfall insists that teams wait until step four out of six to test their products. Outside of the software industry, the testing phase could mean showing a new website design to a client, A/B testing content, or taking any number of steps to gain empirical data on the viability of the project. At this point, the project has likely taken considerable time to complete, so large revisions could cause significant delays.

The agile methodology was created in direct response to this principle of Waterfall. Critics of Waterfall felt that there was too much room for problems to remain unnoticed until the project neared completion, which left large, costly changes as the only solution. If you feel that frequent testing would serve your team better, implement testing at the end of every project stage so that you don’t move forward until you know things are working. Or consider a different project management methodology that encourages reflection and revision throughout the process.

Navigating Waterfall model advantages and disadvantages

The Waterfall methodology has had critics and supporters since its inception, but it remains relevant today even as other methodologies have evolved to account for many of its flaws. If your team is small and your projects are consistent and predictable, then Waterfall could provide the ideal framework for keeping your team organized and on track.

If not, don’t be afraid to customize a project management methodology to make it right for you. With Lucidchart, you have free rein to create a structure that will work best for your team and its unique needs.

Track your Waterfall process or any methodology you choose.

Sign up for Lucidchart today!

The Waterfall Model was the first Process Model to be introduced. It is also referred to as a linear-sequential life cycle model. It is very simple to understand and use. In a waterfall model, each phase must be completed before the next phase can begin and there is no overlapping in the phases.

The Waterfall model is the earliest SDLC approach that was used for software development.

The waterfall Model illustrates the software development process in a linear sequential flow. This means that any phase in the development process begins only if the previous phase is complete. In this waterfall model, the phases do not overlap.

Waterfall Model - Design

Waterfall approach was first SDLC Model to be used widely in Software Engineering to ensure success of the project. In "The Waterfall" approach, the whole process of software development is divided into separate phases. In this Waterfall model, typically, the outcome of one phase acts as the input for the next phase sequentially.

The following illustration is a representation of the different phases of the Waterfall Model.

The sequential phases in Waterfall model are −

• Requirement Gathering and analysis − All possible requirements of the system to be developed are captured in this phase and documented in a requirement specification document.

• System Design − The requirement specifications from first phase are studied in this phase and the system design is prepared. This system design helps in specifying hardware and system requirements and helps in defining the overall system architecture.

• Implementation − With inputs from the system design, the system is first developed in small programs called units, which are integrated in the next phase. Each unit is developed and tested for its functionality, which is referred to as Unit Testing.

• Integration and Testing − All the units developed in the implementation phase are integrated into a system after testing of each unit. Post integration the entire system is tested for any faults and failures.

• Deployment of system − Once the functional and non-functional testing is done; the product is deployed in the customer environment or released into the market.

• Maintenance − There are some issues which come up in the client environment. To fix those issues, patches are released. Also to enhance the product some better versions are released. Maintenance is done to deliver these changes in the customer environment.

All these phases are cascaded to each other in which progress is seen as flowing steadily downwards (like a waterfall) through the phases. The next phase is started only after the defined set of goals are achieved for previous phase and it is signed off, so the name "Waterfall Model". In this model, phases do not overlap.

Waterfall Model - Application

Every software developed is different and requires a suitable SDLC approach to be followed based on the internal and external factors. Some situations where the use of Waterfall model is most appropriate are −

• Requirements are very well documented, clear and fixed.

• Product definition is stable.

• Technology is understood and is not dynamic.

• There are no ambiguous requirements.

• Ample resources with required expertise are available to support the product.

• The project is short.

Waterfall Model - Advantages

The advantages of waterfall development are that it allows for departmentalization and control. A schedule can be set with deadlines for each stage of development and a product can proceed through the development process model phases one by one.

Development moves from concept, through design, implementation, testing, installation, troubleshooting, and ends up at operation and maintenance. Each phase of development proceeds in strict order.

Some of the major advantages of the Waterfall Model are as follows −

• Simple and easy to understand and use

• Easy to manage due to the rigidity of the model. Each phase has specific deliverables and a review process.

• Phases are processed and completed one at a time.

• Works well for smaller projects where requirements are very well understood.

• Clearly defined stages.

• Well understood milestones.

• Easy to arrange tasks.

• Process and results are well documented.

Waterfall Model - Disadvantages

The disadvantage of waterfall development is that it does not allow much reflection or revision. Once an application is in the testing stage, it is very difficult to go back and change something that was not well-documented or thought upon in the concept stage.

The major disadvantages of the Waterfall Model are as follows −

• No working software is produced until late during the life cycle.

• High amounts of risk and uncertainty.

• Not a good model for complex and object-oriented projects.

• Poor model for long and ongoing projects.

• Not suitable for the projects where requirements are at a moderate to high risk of changing. So, risk and uncertainty is high with this process model.

• It is difficult to measure progress within stages.

• Cannot accommodate changing requirements.

• Adjusting scope during the life cycle can end a project.

• Integration is done as a "big-bang. at the very end, which doesn't allow identifying any technological or business bottleneck or challenges early.