The concept of kanban is poorly understood by many. In most cases, the level of understanding between two experts discussing kanban will vary, even if they both gain something of value from the conversation.
So, what exactly is Kanban – a card, a board, a system or a method?
The short answer is – all of them.
Both the hiragana (Japanese) and the Kanji (Chinese) scripts serve as the basis for the word “kanban”. It means “signal card” in hiragana, “sign” or “huge visual board” in kanji.
The concept of “kanban,” beyond its ancient roots, was popularised by Taiichi Ohno (former Toyota vice president) in the 1940s. They pushed the concept of just-in-time (JIT) manufacturing in Toyota, which uses kanban cards as a signal between two dependent processes to encourage a smoother flow of vehicle parts between processes, taking cues from how supermarkets stock their shelves. This provided early and consistent value, using collaborative and self-managing teams. Originally intended as a simple signal card, the concept of kanban has evolved through time. Initially developed for the industrial sector, the “Kanban System” has since found widespread adoption in the IT sector and software development on the strength of three distinguishing characteristics:
- Visualization of work items – using signal cards or some other means.
- A pull-based system, where work is pulled by the following process, based on available capacity, rather than pushed by the previous process.
- Enforcing Work in Progress (WIP) Limits – limiting total work in progress narrows the team focus, streamlining the flow of work and improving product quality.
One crucial notion advocated by Kanban is the restriction of the number of “Work in Process” (WIP) elements. Too many tasks in progress can provide the impression of productivity, but they ultimately yield nothing beneficial to the end user! Instead of starting something new, I’ve found that it’s best to focus on bringing the user story to a close. My favourite quote when applying work-in-progress limits is:
Stop Starting. Start Finishing!
Visual boards are commonly used by teams utilising the Kanban System for tracking and managing the flow of work, typically called a Kanban Board. Scrum practitioners may view the Scrum board as a simplified version of the Kanban Board.
Now, what about the Kanban method?
David J. Anderson popularised the phrase “Kanban Method” to describe the management approach he developed over the past decade to enhance service delivery and make businesses more “fit for purpose.” However, it is not a process framework for software development or a project management technique. It’s a collection of guidelines for gradual, organic shifts in your company. It will not be used in place of your current process, whether Scrum or waterfall, but rather to enhance it to serve its intended purpose better.
Kanban has developed from a signal card system into a management technique. Still, its core tenets of a focus on visibility and a pull-based approach to organising work remain the same.
The six critical practices outlined in the Kanban Method include:
- Visualize your work – You want to see cards move in status from one column to the next.
- Limit work-in-progress – It’s about finishing work!
- Measure and Manage flow – We don’t manage people, instead we manage the flow of work by keeping the highest priority items on the top of the list. Team members pull one item at a time from the list, minimizing context switching.
- Make policies explicit.
- Implement feedback loops.
- Improve collaboratively, and evolve experimentally.
In addition to these six practices, the Kanban Method uses the following concepts: Work item types, Classes of service, Swim lanes, an Expedite Lane, a Ready Queue or Input Buffer, a Replenishment meeting, and the Daily Kanban (runs differently than Daily Scrum). Throughput, Cycle/Lead time distribution, control charts, and cumulative flow diagrams are some of the most important metrics used by Kanban teams to enhance the flow of work (and service delivery).
We can say that the Kanban Method, which employs a Kanban board, is the most robust and developed notion among the many kanban terminologies. It aids teams in adopting a pull-based approach to task management as part of an evolutionary shift toward increased agility.
Reference: Kumar, S., 2016. Kanban – A Card, Board, System or a Method? https://www.linkedin.com/pulse/kanban-card-board-system-method-sanjay-kumar/ [Accessed 14 08 2022]