When Kanban emerged as a popular practice, it was often presented as an alternative to Scrum. However, as Torbjörn Gyllebring emphasized years ago, Kanban is not a replacement for your process. Instead, it serves as a tool for process enhancement, adaptable to various workflows. This adaptability is one of its greatest strengths, and it’s why I’m such a proponent of Kanban.
However, some early Kanban adopters, in their eagerness to depart from Scrum’s ceremonies, went too far and removed all constraints and trade-offs. “Kanban—love it! No planning, no sprints, no constraints—it’s just our board, and work flows as fast as it flows… Nice!” But, to be honest, a board without a Work In Process (WIP) limit isn’t really a Kanban board. Let me explain why.
- Blocked is not a column
- Todo - Doing - Done is not your process
- Done? There’s no Done
- Colors speaks volumes - use them deliberately
- It’s not a kanban board if you don’t have a WIP limit
- Walk the board from right to left
- Focus on the work - not the workers
- And for the love of everything holy - please tear off the post-it’s the correct way!
Limitless Boards
Most of the Kanban boards I’ve encountered lack limits on the amount of work they can contain. They simply accommodate as much work as deemed necessary for any given situation.
While this might seem convenient and “easy” initially, it’s actually detrimental to focus and workflow efficiency.
Moreover, a board without a WIP limit can’t truly be called a Kanban board. The fundamental principles of Kanban, since its inception, include:
- Visualize - Represent work visually on a board
- Limit work in process - Establish some form of WIP limit
- Help work to flow - Manage, prioritize, and facilitate the flow of work through the process
Why Address This Issue?
Work in process (or “in progress”) refers to tasks currently being worked on—those present on the board. It’s widely acknowledged that reducing concurrent tasks accelerates individual task completion. Although concepts like Little’s Law may seem complex at first, they underscore the importance of WIP limits.
Operating without WIP limits essentially means accepting an unlimited influx of tasks—a scenario akin to an open-ended sprint backlog in Scrum, a practice no prudent team would endorse. While Kanban emphasizes flow over iteration, this doesn’t negate the necessity of constraints.
Addressing the Issue: Implementing WIP Limits
The remedy lies in establishing WIP limits—a simple yet nuanced endeavor. Here are common approaches:
- Column-based Limits: Restrict the number of tasks in specific workflow stages by displaying numerical limits above columns.
- Board-wide Limits: Enforce a maximum limit for the entire board, fostering a focus on completing tasks rather than starting new ones.
- Individual Limits: Assign a limit per team member, delineating their capacity to work on concurrent tasks.
Selecting an appropriate WIP limit necessitates deliberation. Rather than viewing it as a rigid rule, consider it a catalyst for discussion. Strive for a lower limit, prioritizing efficiency and flow.
Determining an Optimal WIP Limit
The ideal WIP limit varies based on team dynamics and context. While external consultants may offer guidelines, the team’s intimate knowledge of its workflow is indispensable. Adhering to principles like “Stop Starting - Start Finishing” and aiming for lower limits facilitates smoother workflows.
Indicators like idle tasks (for high WIP limits) and idle workers (for low WIP limits) highlight imbalances. An experimental approach, advocated by Dr. Don Reinertsen, involves iteratively adjusting WIP limits to optimize flow.
Conclusion
Kanban’s essence lies in three principles: visualization, WIP limits, and flow facilitation. Without WIP limits, teams risk losing focus, prioritization, and efficiency.
A true Kanban board mandates WIP limits. Embrace constraints—they catalyze productivity and streamline workflows. Implement WIP limits tailored to your team’s needs, fostering a culture of continuous improvement.
If you found this post insightful, explore more related content below.
- Blocked is not a column
- Todo - Doing - Done is not your process
- Done? There’s no Done
- Colors speaks volumes - use them deliberately
- It’s not a kanban board if you don’t have a WIP limit
- Walk the board from right to left
- Focus on the work - not the workers
- And for the love of everything holy - please tear off the post-it’s the correct way!