What is the waterfall model?

While the waterfall design model is typically used in software development, it can apply to product design lifecycle processes in general. Being a linear model, the waterfall model progresses through the following sequential stages:

1. Requirement gathering and analysis: This stage involves planning resource allocation, defining end goals, setting deadlines for each phase and establishing guidelines.
2. Analysis: Financial and resource audits are conducted during this phase. It may also involve examining use-cases and specifications to generate product models.
3. System design: Involves creating documentation for the product model design. This may involve choosing a programming language to use, hardware, software architecture and data sources.
4. Implementation: The system’s design is created according to the documentation specifications.
5. Integration and testing: The product undergoes a quality assurance test to identify and resolve potential issues.
6. Deployment of the system: The final product is released onto the market for end-users and customers.
7. Maintenance: The product is improved and refined over time with patches, new versions and more advanced models.

Waterfall model advantages and disadvantages

In this next section, we explore some of the pros and cons of using the waterfall model to develop a product. Understanding these advantages and limitations can help businesses determine whether this approach suits their needs or if alternative models may be more effective.

Waterfall model advantages

The waterfall model offers several key benefits, making it a practical choice for certain product development scenarios.

Follows a clear, straightforward structure

The waterfall model’s clear sequential-linear progression makes it easier for teams to understand. Other methodologies often require a more abstract understanding of the product development cycle, and methodologies like Agile delivery may require additional training or certifications. The waterfall model’s simplicity means less time is spent learning the process, allowing teams to focus on execution.

Helps to define the product development goal early on

The waterfall model’s linearity requires product developers to define their development goals at the outset. This can contribute to a more focused approach to product design, ensuring the key resources required for development, necessary features and end-use cases are identified and prioritised from the beginning.

Enables streamlined information transfer between teams

The waterfall model involves breaking down product development into clear project milestones which must be completed in order to progress to the next one. This means that once one team completes their part of their project, they can pass that information onto the team responsible for the next step. This generally makes product development communications clearer; reducing the need for back-and-forth exchange of information.

Useful for predictable design outcomes

The waterfall model is ideal for managing projects with routine or repetitive design elements. Its structured approach makes it easier for teams to manage predictable development cycles efficiently.

Potential for automation

The model’s structured nature lends itself well to automation. For example, businesses can use natural language processing to automate documentation and hand-over summaries or predictive analytics to anticipate project timelines, identify bottlenecks and optimise resource allocation.

Waterfall model disadvantages

While the waterfall model offers structure and simplicity, it also has significant limitations that businesses should consider:

Difficult to adapt to change

While its linear approach might make each stage more streamlined, the waterfall model makes it difficult to adapt to changes once a stage is completed. When a team completes one stage, it can be difficult to return to previous stages. For businesses looking to keep their products up-to-date and relevant to their customers and end-users, this could pose a problem. In contrast, businesses using more flexible models can enable faster adjustments based on customer feedback.

Does not involve the end-user in decision-making processes

The model’s inflexibility limits opportunities to incorporate end-user or customer feedback into the decision-making process. This feedback could be especially important if it is in response to a product prototype. Since the waterfall model involves setting goals early on and planning resource allocation in advance, any changes to the product’s development could prove costly.

Testing only occurs after completion

In the waterfall model, testing happens only after the product is fully developed. Given the model’s inflexibility, this can require considerable time and resources. In worst case scenarios, some product lifecycles may need to re-start from the beginning to incorporate new features or changes. 

Additionally, involving customers and end-users in the testing process can provide valuable insights to help keep products competitive and aligned with market demands, which the waterfall model struggles to integrate efficiently.

Alternatives to using the waterfall model in product development

While the waterfall model may suit small teams with predictable design tasks, businesses aiming to stay competitive, incorporate end-user feedback, and adapt to fast-changing markets might benefit from alternative models such as Agile or Lean methodologies. Let’s explore these two popular models:

Agile methodology

Agile product management is built on four key principles:

• Prioritising individuals and interactions over processes and tools
• Focusing on working software over comprehensive documentation
• Encouraging customer collaboration over contract negotiation
• Responding to change over following a plan

Agile methodologies allow product teams to make swift and effective changes to products already in the process of being made. Unlike the waterfall model, which restricts teams from revisiting earlier stages due to its linear structure, Agile’s iterative approach supports flexibility and adaptability, which is particularly important to fast-paced industries.

Agile enables product developers to break down projects into bite-sized chunks, known as ‘sprints’, where a team will work to quickly resolve a specific task in the process. In scrum meetings, employees can have regular face-to-face meetings to communicate and exchange information about project developments.

This methodology fosters cross-departmental collaboration, which helps product developers to fix problems as they emerge or implement new features that could improve a product’s competitiveness on the market. 

Lean approaches to product development

Some Agile teams use what’s known as a Lean approach. Lean methodology focuses on eliminating waste from the product development process, while maximising the product’s value to end-users and customers. Waste according to Lean management methodology includes:

• Product defects
• Overproduction
• Waiting time for deliveries of resources
• Non-utilised talent
• Unnecessary transport, such as long-distance resource hauling
• Inventory, such as overstocking and supply chain issues
• Motion, including unnecessary energy usage of machinery, transport and employee effort
• Excess processing, such as employees spending too long on unnecessary features of a product

During product development, Lean teams continually analyse the efficiency of a product and identify areas for improvement. Lean approaches can help a business to become more sustainable by optimising resource usage and minimising transport waste.

Waterfall models can help product developers deliver simple tasks while keeping communication clear and methodical. However, for products developed in fast-changing industries, teams may benefit more from using Agile and Lean approaches. These methodologies can help save businesses valuable time and money while keeping products relevant to their customer base.