For almost three quarters of a century, project management methodologies have evolved to embrace the one true constant - change. Two of the most popular and core methodologies are Waterfall and Agile. The Waterfall model consists of a linear progression of project management phases, whereas the Agile model emphasizes iterative and collaborative techniques. Though the philosophies of each model vary greatly, the underlying goal of successfully completing projects, remains the same.
A critical attribute of an effective project manager, in addition to leadership and communication skills, is a deep level of knowledge and competence in project management methodologies. The traditional Waterfall model was developed in the 1970s and consists of phases, with dependencies on artifacts delivered by the previous phases. The phases in sequence consist of: Requirements, Design, Implementation, Verification, and Maintenance. In order to start the Implementation phase for example, a requirements specification document from the Requirements Phase, and a system design and architecture diagram from the Design phase, are required. Several decades later, in the early 2000s, the Agile model arose out of a need to speed up delivery of projects to customers. A key highlight of the Agile model is to obtain customer feedback quickly in order to iteratively and continuously improve the end product.
The Waterfall model is often used with smaller projects when requirements are clear and set in stone, or when scope, schedule, and cost constraints demand a formulaic outcome. A clear end-to-end schedule can be developed with milestones for strict tracking and controlling. Tollgates or checkpoints are required for approval before proceeding to the next phase, guaranteeing comprehensive documentation and quality assurance checks. The abundance of documentation allows for streamlined on-boarding – especially during times of unexpected staff turn-over. The rigidity of the non-overlapping phased process ensures easier management of the project over other models.
The Agile model on the other hand is best employed for longer running or maintenance projects where requirements are dubious or prone to changes. A customer often does not know what they want until they see a shippable increment that sparks ideas and feedback. Agile methodologies stress incremental and frequent releases of the project or product so that a feedback loop can be immediately initiated in an effort to deliver exactly what’s needed. Client satisfaction levels may maintain high levels due to the constant interaction between the project team and stakeholders. Anecdotally, project teams report high levels of satisfaction with Agile since the increments that are being completed receive quick responses – making their contributions feel valued. A focus on the highest priority and value backlog items ensures efficient and low-waste efforts.
The rigidity of the Waterfall model adds complexity and some chaos when changes are introduced at subsequent phases. In some cases, stoppage of work is required while each phase is revisited, and artifacts and documentation are updated. The sequential nature of the Waterfall model can be off-putting for clients who must wait until the latter phases to see their requirements implemented. Any misinterpretation of those requirements can lead to extensive re-work after weeks or months of effort, not to mention angst-ridden attitudes from certain clients. With testing delayed until the Verification phase, any functionality or form related bugs that are found, have the potential to critically derail the schedule and budget.
One of the main drawbacks of the Agile model is the unpredictability of scope, which leads to ambiguous schedule and budget. This resource allocation fuzziness can be a nightmare for inexperienced project and program managers. Lack of a finite completion date can add pain-points to matrix organizations that have multiple programs to prioritize and execute. With scope changes occurring as frequently as the feedback loop, it can be difficult to on-board new team members since documentation may not be as detailed or clear. A greater level of communication and responsiveness to customer needs is required in Agile projects – often including the entire project team – and increasing costs.
The best project managers can quickly adapt to change. No matter the methodology used, it’s important to keep an eye on the end goal – providing a substantial benefit or value to the client. Whether selecting the rigid but easy to manage Waterfall model, or the iterative and customer obsessed Agile workflow, an open mind and willingness to adapt is required. This is why many project managers embrace a hybrid Waterfall-Agile approach.
References
Project Management Institute (2021). Beyond Agility: Flex to the Future. Pulse of the Profession®.
Conrad, A. (2017, July 13). The History of Project Management and Predictions for the Future. Capterra Blogs.