Agile vs Waterfall
February 28, 2024
Overview
Agile and Waterfall are popular alternatives to the organization of tasks in project management. They are most prominently associated with software development teams, but they can be applied to other industries and management teams as well.
- Agile: This development methodology is known for a breakdown of smaller tasks that should be completed within 1-2 week iterations of work. This smaller breakdown of tasks results in a more iterative work style with more frequent feedback that enables quicker adjustments given new information.
- Waterfall: This development methodology provides a clearer picture of the dependencies between tasks. It is less forgiving to missed deadlines.
It's important to see that both of these methodologies handle the following in different ways:
- Task deadlines.
- Task size (breakdown within larger tasks/projects).
- Task prioritization at a micro-level.
Regardless of which methodology is chosen, task scheduling (as a whole) always takes the form of a Directed Acyclic Graph. This inherent DAG data structure is more difficult to see in an Agile methodology because of its openness to change and adaptability, but it's always there. This DAG structure also applies to the scheduling of projects (and everything).
Table of Contents
Comparison
| Agile | Waterfall | |
|---|---|---|
| Philosophy | Emphasizes adaptability and responsiveness to change. | Focuses on thorough planning at the beginning and a sequential design process. |
| Approach | Iterative, dynamic, open to change. | Linear phases, continuous, closed to change. |
| Project Structure | Broken into sprints (a.k.a. iterations) with each sprint intended to deliver at least one unit of complete work. | Broken into distinct phases (i.e. planning, design, implementation, testing, operations). |
| Flexibility | High. Changes can be made anytime (although, earlier is always better). | Low. This is due to the greater approval process that is traditionally inherent in the methodology. |
| Feedback Loop | Continuous feedback from stakeholders is encouraged. | Feedback is typically gathered at the end of the project. |
| Documentation | Less emphasis on documentation and more emphasis on working software. | More emphasis on documentation at each phase. |
| Cost and Time Estimation | Estimations adjust throughout. | More time taken at the beginning to provide an accurate estimation. |
| Outcome Predictability | Buffer is required. Less predictable. | More predictable, assuming the initial planning was correct. |
| Use Case | Projects with more unknowns. | Projects with fewer unknowns. |
| Success Measurement | Strong focus on the final product with less focus on duration. | Strong focus on the product, accuracy of the initial plan, timeline, and budget. |
Table template created by ChatGPT of OpenAI.
Agile
The Agile management style is about breaking changes into small 1-2 week iterative tasks and embracing change. Agile specifically advocates to focus more on writing software, rather than writing documentation. However, documentation can be seen as its own task at the end of the project to support operations and future work, rather than an integral process throughout all phases.
Enjoy a deeper dive into the Agile development lifecycle.
Waterfall
Although Waterfall advocates for a sequential design process, the intention is for these designs throughout the project to introduce little-to-no additional work. That work should have been allocated at the beginning where the bulk of the planning took place. Waterfall advocates for a tough approval process at each phase in order to minimize the chance of any track-back in the phases, which would require additional approval.
Enjoy a deeper dive into the Waterfall development lifecycle.
Hybrid
There's nothing stopping you from adopting a Waterfall methodology at the beginning of a project in order to maximize the planning phase, then moving onto an Agile methodology in order to maximize agility in case new information compels design changes. This hybrid methodology can be approached as entirely Agile, simply with a deeper planning phase to shed light on unknowns.
Conclusion
The exact methodology used should depend on the team, their work style, and the manager's management style. The goal is to manage resources effectively.
To be updated with diagrams.