3 October 2023 (updated: 22 May 2024)
Chapters
Kanban vs. Scrum: discover the differences, pros, and cons of the two most popular Agile methodologies.
There is no doubt that Agile revolutionized the project management world as a methodology that emphasizes adaptability and collaboration. Subsequently, there is a broad variety of agile frameworks, with Scrum and Kanban standing out as the two most commonly utilized. In today’s product development world that requires strong project management principles, adaptability, and flexibility, choosing the right agile framework may play a crucial part in your project’s success.
Scrum provides structure and guidance, and Kanban gives a great visual representation of the project’s progress and workload. So the main question is: which one’s better, Scrum or Kanban? In this article, we’ll compare those frameworks so you can make the best choice for your next project.
Scrum | Kanban | |
Key concepts | Structure, efficiency, and predictability | Transparency, task visualization, and adaptation |
Work cycle | Iterations - usually two-week-long sprints | Continuous flow |
Roles | Scrum Master, Product Owner, Development Team | No defined roles but there is often an Agile Project Manager |
Artifacts | Product backlog, Sprint Backlog, Increments | WIP Limit, Kanban Board |
Events | Sprint Planning, Sprint, Daily Standup, Sprint Review, Sprint Retrospective | Not specified, usually daily stand-ups and replenishment meetings |
Planning & prioritization | Defined before each sprint | Just-in-time planning, constant reprioritization as needed |
Board | Reflects Sprint backlog, is reset after each sprint | Reflects the whole project, never reset |
Pros | Clear expectations in the requirements, deadline, and roles | Adaptability, workload visualization, and limiting work in progress |
Cons | Hard to respond to unexpected challenges, short cycles may lead to stress | May lack structure and clear expectations, harder for inexperienced teams |
Scrum is undoubtedly the most commonly used Agile framework. The main objectives of Scrum include collaboration, iteration, and transparency. It is also renowned for its efficiency and predictability, making it a great choice for various projects from different industries. It also provides a lot of guidance and structure, making it a common choice for teams transitioning into agile project management.
Kanban, originally stemming from manufacturing, found its way to software development. The core of this methodology is workload visualization and optimization represented by the Kanban Board and WIP Limits. Kanban’s key values are transparency and adaptation. The visualization of the workload makes it easy to prioritize tasks and identify blockers.
The first difference between Scrum and Kanban is the work cycle. Scrum is based on the idea of iteration, presented by Sprint. Sprint is usually a two-week period during which the team works on a set of tasks from the product backlog. The goal of each sprint is to deliver an increment - a product element that is potentially shippable. Task changes are discouraged until the sprint ends.
In contrast, Kanban utilizes a more fluid approach - a continuous flow of tasks from the “To Do” column. There are no fixed timeframes, allowing the teams to adapt to changing priorities, That’s why Kanban is particularly suitable for a project their responsiveness and adaptability are crucial.
The roles play an important part in Scrum and include Scrum Master, Product Owner, and the Development Team. The Scrum Master is a facilitator who makes sure the team meets the Scrum objectives and removes bottlenecks. The Product Owner is responsible for prioritizing and Managing the product backlog, and the Development Team is responsible for delivering the work.
In Kanban, there are no specific roles, however, the Agile Project Managers are often a part of the team to help prioritize tasks and meet deadlines. The whole team works together to complete tasks from the Kanban Board. The lack of predefined roles fosters more ownership and results in more flexible, self-organizing teams.
In Scrum, the key artifacts revolve around planning and delivery. In the Product Backlog all desired features, improvements, and bug fixes are listed and prioritized. The tasks from the Product Backlog are often broken down into smaller tasks and moved into a Sprint Backlog during sprint planning. Sprint Backlog represents the scope of work that the team completes during one sprint. The main goal of each Sprint is to deliver an Increment, which is a small product segment that by the end of each sprint should be functional and ready for a potential release.
On the other hand, Kanban puts emphasis on continuous flow. The main artifact of the framework is the Kanban Board. It consists of cards representing each taste and column, defining the stage of the tasks, such as To Do," "In Progress," and "Done". The Board is a visual representation of the real-time status of each task and the overall project progress. Another Key artifact of Kanban is the WIP (Work In Progress) Limit, which is the maximum number of tasks that can be in progress at the same time. WIP Limits reduce the number of "nearly done" tasks and encourage a "get things done" approach. WIP Limits prevent the team from becoming overloaded and help identify blockers and bottlenecks.
There are several defined events in Scrum, that include the Sprint Planning meeting, where the team selects the set of tasks from the Product Backlog to complete in the Sprint. During the sprint, Daily Standup meetings help sync up and resolve current issues. At the end of each sprint, there are two more meetings: Sprint Review, where stakeholders review the Increment, and Sprint Retrospective, where the team discusses what went well, and identifies room for improvement.
In Kanban, there are once again no specific events. Usually, there is a Daily Standup meeting to discuss progress and resolve any issues. There is also a regular Replenishment Meeting to review the backlog (the “To-do” column of the Kanban board). As Kanban is a more fluid and adaptive framework, the teams can adapt the meeting to their specific needs. In Kanban, there is also more room for asynchronous communication compared to Scrum.
In Scrum, planning happens at the beginning of each sprint at the dedicated meeting. The team gathers to choose, break down, and estimate tasks from the Product backlog and then move them to the Sprint backlog. The team agrees to finish certain tasks during one iteration(sprint). There are no changes in the tasks during the sprint unless there is a sudden change of priorities mid-sprint. Then, the current sprint ends, and the planning process is restarted.
In Kanban, there are no sprints, as the framework relies on the continuous flow approach. Planning relies on the prognosis and is based on the size and type of the tasks and other factors. In Kanban, there is a pull system - when one task is finished, the team can “pull” the next one based on its priority. Then, based on type of the task you can plan the start and end date of the task.
Both frameworks utilize boards to visualize tasks. The Scrum board is based on the sprint backlog and is reset after each sprint. The workload is defined before each sprint, therefore the team cannot add new tasks to the sprint backlog during a sprint. The goal is to get everything in the Done column by the end of each sprint.
In Kanban, there is one board for the duration of the whole project, and it remains continuous. If the WIP Limits are full, a new task can only be started when another is completed. This approach emphasizes delivery speed and prevents work overload.
Both Kanban and Scrum are effective frameworks with many beloved fans. Kanban’s main strength is adaptability and the continuous flow approach that allows teams to respond to changing priorities. The Kanban board provides a bird's view of the project's progress and is an excellent management system that helps the team tackle the bottlenecks and speed up the development process. Limiting work in progress prevents members of the team from becoming overwhelmed.
On the other hand, Scrum is a more structured framework and one of the main benefits of that is a fixed timeframes that emphasize predictability and effectiveness. Time-bound iterations foster regular progress, improvement, and feedback. Set roles and ceremonies provide clear ownership and accountability. Scrum also provides a clear expectation of what needs to be done in a certain amount of time.
Both Frameworks, despite many advantages, have their own set of cons. Scrum sprint cycles and fixed backlogs are not designed to accommodate unexpected shifts of priorities or urgent changes. Fixed roles and responsibilities may prevent team members from taking full responsibility and make them focus on their scope, rather than on the bigger picture. On the other hand, less experienced teams may be overwhelmed with Scrum rules, that’s why it is crucial that Scrum Master overlooks the entire process and educates the team. Lastly, a fast-paced, short work cycle often leads to stress and fear of failure, especially by the end of each sprint.
Too much structure may be complicated for inexperienced teams, but so can little structure be. That’s why Kanban, although it may appear easier to understand, may be harder for inexperienced teams. The absence of clear roles, ceremonies, and changing scope, can often be misleading and lead to ambiguity. It also requires more team self-discipline. Often, Kanban is viewed only as a visualization tool, with a disregard for other elements and principles of this framework.
In response to both the pros and cons of Kanban and Scrum, there is a hybrid framework - Scrumban. It takes structure and routines from Scrum and the adaptable, flexible nature of Kanban. Combining those frameworks brings in increased efficiency and effectiveness, however, to make it work, the team needs to understand the principles of both frameworks.
3 September 2024 • Maria Pradiuszyk