22 Differences between Scrum and Kanban
Scrum and Kanban are both popular agile frameworks used in software development and project management, but they have some key differences in terms of their principles, practices, and approaches to workflow management. Here’s a comparison of Scrum and Kanban:
- Philosophy and Origins:
Scrum: It originated from the rugby term and emphasizes teamwork, collaboration, and iterative progress. Scrum divides work into fixed-length iterations called sprints, typically two to four weeks long.
Kanban: It means billboard in Japanese, Originating from lean manufacturing principles, Kanban focuses on continuous delivery and flow. It emphasizes visualizing the workflow, limiting work in progress (WIP), and minimizing waste.
2. Roles and Responsibilities:
Scrum: Defines specific roles, including Scrum Master, Product Owner, and Development Team. Each role has well-defined responsibilities.
Kanban: Typically has fewer prescribed roles. It may have roles like the Kanban Lead, but responsibilities can be more flexible and are often defined by the team.
3. Planning and Scheduling:
Scrum: Works in fixed-length iterations (sprints) with a defined set of backlog items to be completed within each sprint. Planning occurs at the beginning of each sprint.
Kanban: Generally does not have fixed iterations. Work is pulled as capacity allows. There is a continuous flow of work, and planning can happen at any time.
4. Work Prioritization:
Scrum: Prioritizes work through a backlog, and the team commits to delivering a set amount of work during each sprint.
Kanban: Prioritizes work based on the team’s capacity and the needs of the system. Work items can be reprioritized at any time.
5. Iterations:
Scrum: Work is organized into fixed-length iterations, and changes to the scope are generally not allowed during a sprint.
Kanban: Works on a continuous flow basis, allowing for flexibility in changing priorities and scope at any time.
6. Metrics and Continuous Improvement:
Scrum: Uses metrics like velocity to measure the team’s productivity. Continuous improvement is typically addressed in sprint retrospectives.
Kanban: Uses metrics such as lead time and cycle time to measure the time it takes to complete a task. Continuous improvement is an ongoing process and is embedded in the Kanban principles.
7. WIP (Work In Progress) Limits:
Scrum: Does not explicitly enforce work-in-progress limits, but teams are encouraged not to overcommit during sprint planning.
Kanban: Enforces WIP limits to optimize flow and identify bottlenecks. This ensures that the team does not take on too much work at once.
8. Cadence:
Scrum: Operates on a fixed cadence with regular sprint planning, sprint review, and sprint retrospective meetings. The fixed iteration length provides a rhythm for the team.
Kanban: Operates continuously without fixed timeframes. Work items move through the workflow as they are ready, and there are no predefined ceremonies.
9. Changes During a Cycle:
Scrum: Generally discourages changes to the sprint scope once the sprint has started to maintain focus and stability.
Kanban: Allows for changes to priorities and scope at any time, providing more flexibility to respond to evolving requirements.
10. Roles in Detail:
Scrum:
- Scrum Master: Facilitates the Scrum process and removes impediments.
- Product Owner: Represents the stakeholder and prioritizes the backlog.
- Development Team: Self-organizing and cross-functional, responsible for delivering the product increment.
Kanban:
- Kanban Lead or Manager: Facilitates the Kanban process, ensures adherence to policies, and monitors metrics.
- Team: Often cross-functional, with members collectively responsible for delivering work.
11. Estimation:
Scrum: Often involves estimating the effort required for each backlog item using techniques like story points.
Kanban: Generally does not prescribe specific estimation practices, and work items can be pulled based on priority and capacity without explicit estimation.
12. Visibility and Metrics:
Scrum: Relies on burndown charts, velocity, and sprint backlogs for visibility and metrics.
Kanban: Emphasizes visualizing the workflow on a Kanban board and uses metrics like lead time, cycle time, and WIP limits to monitor and improve performance.
13. Size of Teams:
Scrum: Works well with smaller, cross-functional teams (typically 5–9 members).
Kanban: This can be applied to both small and large teams, and the team size can be more flexible.
14. Ceremonies:
Scrum: Has prescribed ceremonies such as sprint planning, daily stand-ups, sprint review, and sprint retrospectives.
Kanban: Typically has fewer prescribed ceremonies, and teams have the flexibility to decide on the ceremonies that suit their needs.
15. Applicability:
Scrum: Well-suited for projects with a clear product backlog, a need for fixed-length iterations, and a desire for a defined structure.
Kanban: Well-suited for continuous delivery, support, and maintenance work, and situations where requirements evolve frequently.
16. Handling Changes:
Scrum: Changes to the sprint backlog are generally discouraged during a sprint to maintain stability, with adjustments made in the following sprint.
Kanban: Embraces changes at any time, allowing for continuous adaptation to evolving priorities and requirements.
17. Risk Management:
Scrum: Identifies and mitigates risks during sprint planning and reviews, focusing on addressing potential issues within the fixed sprint timeframe.
Kanban: Addresses risks as they arise, providing a more continuous and adaptive approach to risk management.
18. Dependency Management:
Scrum: Teams often work on user stories independently, and dependencies are managed through backlog prioritization and sprint planning.
Kanban: Visualizes dependencies on the Kanban board and allows teams to manage and adapt to dependencies in real time.
19. Learning and Improvement:
Scrum: Emphasizes continuous improvement through sprint retrospectives, where the team reflects on what went well and what could be improved.
Kanban: Incorporates continuous improvement as an integral part of the process, with teams encouraged to identify and address bottlenecks and inefficiencies on an ongoing basis.
20. Customer Engagement:
Scrum: Involves the Product Owner in backlog prioritization and sprint reviews to ensure alignment with customer needs.
Kanban: Provides continuous visibility to stakeholders through the Kanban board, allowing for real-time feedback and adaptation to changing requirements.
21. Release Planning:
Scrum: Involves release planning at the end of each sprint, where a potentially shippable product increment is delivered.
Kanban: Supports continuous delivery, allowing teams to release new features or improvements as soon as they are completed and tested.
22. Documentation:
Scrum: Advocates for lightweight documentation, with a focus on working software over comprehensive documentation.
Kanban: Encourages just-in-time documentation, with an emphasis on delivering value and minimizing unnecessary documentation.
Choosing Between Kanban and Scrum:
Nature of Work:
- Kanban is often preferred for continuous and unpredictable work, while Scrum is suited for projects with well-defined requirements and a fixed scope.
Predictability vs. Flexibility:
- Scrum provides more predictability with fixed-length sprints, while Kanban is more flexible and can adapt to changes more easily.
Team Structure and Roles:
- If you prefer defined roles and ceremonies, Scrum might be a better fit. If you value flexibility and continuous improvement, Kanban may be more suitable.
In summary, while both Scrum and Kanban share agile principles and values, they have different approaches to managing work, planning, and team roles. Scrum is more prescriptive with fixed iterations and defined roles, while Kanban is more flexible, allowing for continuous delivery and adapting to changing priorities. The choice between Scrum and Kanban often depends on the specific needs, preferences, and constraints of the team or organization. It’s also worth noting that teams can adopt practices from both frameworks, tailoring their approach to suit their unique context (known as a “blended” or “hybrid” approach). A combination of both frameworks is known as Scrumban.