How do you compare waterfall and iterative SDLC project management?

1 Waterfall model

The waterfall model is a linear and sequential process that follows a predefined set of steps from requirements analysis to deployment and maintenance. Each step is completed before moving on to the next one, and there is little or no feedback or change allowed once a phase is done. The waterfall model is suitable for projects that have clear and stable requirements, well-defined scope, and predictable outcomes. It also provides a clear documentation and traceability of the project progress and deliverables. However, the waterfall model can also be rigid, inflexible, and risky, as it does not accommodate changing customer needs, market conditions, or technical challenges. It also requires a lot of upfront planning and design, which can be time-consuming and costly. Moreover, it delays the testing and validation of the software until the end of the project, which can lead to poor quality, defects, and rework.

2 Iterative model

The iterative model is a cyclical and incremental process that breaks down the project into smaller and manageable units or iterations. Each iteration consists of a mini-waterfall cycle that covers all the phases of the SDLC, from planning to testing and deployment. The iterative model allows for frequent feedback, review, and improvement of the software based on the customer and stakeholder input, as well as the lessons learned from previous iterations. The iterative model is suitable for projects that have dynamic and evolving requirements, complex or uncertain scope, and innovative or experimental outcomes. It also enables faster delivery, higher quality, and lower risk, as it validates and verifies the software at each iteration and adapts to the changes and issues. However, the iterative model can also be challenging, demanding, and chaotic, as it requires constant communication, collaboration, and coordination among the project team, customers, and stakeholders. It also involves a lot of rework, testing, and integration, which can be resource-intensive and difficult to manage. Moreover, it may lack a clear vision and direction of the project as a whole, as it focuses on the short-term goals and deliverables.

4 Pros and cons of waterfall and iterative

To summarize, let's look at the pros and cons of waterfall and iterative SDLC project management. Waterfall is a simple and structured process with clear documentation and traceability, as well as well-defined scope and deliverables. However, it is rigid and inflexible, with high upfront planning and design cost, low customer and stakeholder involvement, delayed testing and validation, poor quality, and high risk. On the other hand, iterative is flexible and adaptable, with high customer and stakeholder involvement, frequent testing and validation, low risk, faster delivery and deployment. Though it can be complex and chaotic with low documentation and traceability, undefined scope and deliverables, unpredictable outcomes and benefits, high rework and testing cost, as well as high communication and coordination effort.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?