Intro to Project Management: Agile Project Management Kanban Workflow Visualization WIP Limits Cycle Time

What This Is

Kanban is a visual system for managing work, emphasizing continuous flow and limiting work in progress (WIP). It helps teams deliver value to customers by visualizing the workflow, setting WIP limits, and measuring cycle time. Imagine a software development team using Kanban to deliver new features to customers. They visualize their workflow on a board, set a WIP limit of 10 features in development, and track the time it takes to complete each feature.

Key Terms & Formulas

• Kanban Board: A visual representation of the workflow, showing columns for different stages (e.g., To-Do, In Progress, Done).
• WIP (Work in Progress) Limit: The maximum number of tasks or items allowed in a specific stage of the workflow.
• Cycle Time: The time it takes for an item to move from start to finish in the workflow.
• Lead Time: The time it takes for an item to move from start to finish, including waiting time.
• Throughput: The number of items completed within a given timeframe.
• Lead Time Formula: Lead Time = Cycle Time + Waiting Time
• Cycle Time Formula: Cycle Time = (End Time - Start Time)
• WIP Limit Formula: WIP Limit = (Throughput × Cycle Time)
• Little's Law: Throughput = (WIP Limit / Cycle Time)
• Queue Time: The time an item spends waiting in a stage of the workflow.
• Service Level: The percentage of time a team meets a specific performance goal (e.g., delivering features within a certain timeframe).

Step-by-Step / Process Flow

1. Identify the Workflow: Map out the stages of the workflow, from start to finish.
2. Set WIP Limits: Determine the maximum number of tasks or items allowed in each stage.
3. Visualize the Workflow: Create a Kanban board to display the workflow and WIP limits.
4. Track Cycle Time: Measure the time it takes for items to move through the workflow.
5. Monitor and Adjust: Regularly review the workflow, adjust WIP limits as needed, and identify areas for improvement.

Common Mistakes

• Mistake: Failing to set realistic WIP limits, leading to overcommitting and decreased quality.
• Correction: Set WIP limits based on historical data and team capacity, and regularly review and adjust them.
• Mistake: Not tracking cycle time, making it difficult to identify bottlenecks and areas for improvement.
• Correction: Regularly measure cycle time and use it to inform decisions about WIP limits and workflow adjustments.
• Mistake: Focusing solely on throughput, neglecting the importance of quality and cycle time.

Exam Tips

• Look for the "hidden" WIP limit: In Kanban, the WIP limit is often implicit, so be sure to identify it in the question.
• Understand the difference between cycle time and lead time: Cycle time measures the time an item spends in the workflow, while lead time includes waiting time.
• Be aware of the service level: Kanban teams often aim to meet a specific service level, such as delivering features within a certain timeframe.

Quick Practice Questions

1. If a team has a WIP limit of 5 features and a cycle time of 10 days, what is their throughput? Answer: Throughput = (WIP Limit / Cycle Time) = 5 / 10 = 0.5 features per day
   Explanation: This question requires applying Little's Law to calculate throughput.
2. If a team's cycle time is 5 days and their waiting time is 2 days, what is their lead time? Answer: Lead Time = Cycle Time + Waiting Time = 5 + 2 = 7 days
   Explanation: This question requires applying the Lead Time Formula.
3. If a team has a service level of 80% and wants to increase it to 90%, what should they do? Answer: Increase WIP limits or reduce cycle time
   Explanation: This question requires understanding the relationship between service level, WIP limits, and cycle time.

Last-Minute Cram Sheet

• Kanban: A visual system for managing work, emphasizing continuous flow and limiting WIP.
• WIP (Work in Progress) Limit: The maximum number of tasks or items allowed in a specific stage of the workflow.
• Cycle Time: The time it takes for an item to move from start to finish in the workflow.
• Lead Time: The time it takes for an item to move from start to finish, including waiting time.
• Throughput: The number of items completed within a given timeframe.
• Little's Law: Throughput = (WIP Limit / Cycle Time)
• Queue Time: The time an item spends waiting in a stage of the workflow.
• Service Level: The percentage of time a team meets a specific performance goal (e.g., delivering features within a certain timeframe).
• ⚠️ WIP limits should be based on historical data and team capacity, not arbitrary numbers.
• ⚠️ Cycle time and lead time are not the same – be sure to understand the difference.
• ⚠️ Service level is a key performance metric in Kanban – don't neglect it.