PSK-I Questions and Answers

The Scrum framework already contains elements that create a pull system. In Scrum, the team members "pull" work into the Sprint Backlog during Sprint Planning. They decide which Product Backlog items they will commit to completing based on their capacity and the Sprint Goal. This is a form of a pull system where the team only takes in as much work as they believe they can complete within a Sprint, aligning with Kanban principles that limit Work in Progress (WIP) to optimize flow

Even when using Kanban, Scrum Teams still follow the Scrum framework, which mandates crafting a Sprint Goal during Sprint Planning. The Sprint Goal provides focus and alignment for the team, ensuring that all work contributes toward a common objective, rather than being taken on as needed. References: The Scrum Guide​.

Throughput, which measures the number of items completed over a specific period, is essential forforecasting future delivery rates. By analyzing historical throughput data, Scrum Teams using Kanban can make informed predictions about how many items they can complete by a given date. References: The Kanban Guide for Scrum Teams​​.

Kanban is:

•A strategy for optimizing the flow of value through a process (Option B): Kanban focuses on improving flow and efficiency by using a visual pull system with limited WIP. This strategy helps teams balance demand against throughput and enhance productivity by limiting the number of work items in progress.

Options A (methodology for visualizing workflow) and C (set of practices additive to Scrum) are partially correct but do not fully capture Kanban's purpose. Kanban is not just a visualization tool (A), and while it can be additive to Scrum (C), it is fundamentally a flow-based strategy

The four key flow metrics in Scrum with Kanban are:

•Work in Progress (WIP): The number of items that are currently being worked on.

•Work Item Age: The time that has elapsed since an item started, which helps identify aging work that may need attention.

•Throughput: The number of items completed over a specific period, helping to measure productivity.

•Cycle Time: The total time from when an item starts until it is finished, used to assess how quickly items are moving through the process.

These metrics are essential for understanding and optimizing the flow of work in a Scrum team using Kanban practices

The Work Item Aging Chart is the best chart to determine when a specific Sprint Backlog item that has been started will be finished. This chart provides a visual representation of how long each work item has been in progress, without being completed. It focuses on items that are currently active and helps teams identify which items are aging too much in the workflow, which might require attention to ensure they are completed promptly. The Work Item Aging Chart helps to quickly identify items that might be taking longer than expected, making it ideal for forecasting when a started item willbe finished

When Developers add Kanban to Scrum, the way they use the Sprint Goal during their Daily Scrum can change. In traditional Scrum, the Sprint Goal is a shared commitment for the Sprint. However, in Professional Scrum with Kanban, the focus shifts to the flow of work and delivering value incrementally.

While the Sprint Goal still provides direction, the Daily Scrum may involve discussions about:

Progress towards the Sprint Goal:How are we progressing towards the overall goal?

Work in Progress (WIP):Are we adhering to WIP limits?

Blockers and impediments:What is preventing the team from progressing?

Prioritization:Are we working on the highest-value items?

By focusing on these aspects, the team can ensure that they are delivering value continuously and efficiently.

Little's Lawestablishes a relationship between three flow metrics:Work in Progress (WIP),Cycle Time, andThroughput. It provides insights into how changes in one metric affect the others in a stable system​​.

Little's Law is used to understand and manage flow within a system but isnot a forecasting tool for output or future performance. It assumes a stable and predictable system where the input and output rates are consistent.

Why Not True?

Forecasting requires variability, historical data, and often different statistical models. While Little's Law supports system predictability and capacity planning, it does not directly project future Scrum Team outputs or delivery dates​.

Thus, Little's Law helps teams analyze and optimize flow but is not used for forecasting.

While refining the Product Backlog is essential in Scrum, it is not an essential component specifically for achieving flow in Kanban practices. Achieving flow requires visualizing the workflow, limiting WIP, actively managing WIP, and continuously inspecting and adapting the workflow. Frequent Product Backlog refinement helps with the overall Scrum framework but is not directly tied to the initial goal of achieving flow in a Kanban system

In Professional Scrum with Kanban, the Work in Progress (WIP) limits are set as a policy to maintain a sustainable flow of work. Urgent work emerging does not automatically warrant changing these WIP limits; instead, the team should first discuss how to accommodate the urgent work within the existing constraints. Modifying WIP limits for urgent work could undermine the benefits of a controlled flow, which is why urgent work should not be a reason to change WIP limits during a Sprint

The best answer is option A, which outlines the core Kanban practices for Scrum:

•Visualizing Flow: Helps the team see the state of work items at a glance.

•Limiting Work in Progress (WIP): Prevents overloading the team and promotes focus on completing work.

•Actively Managing the WIP: Ensures the team continuously monitors and manages the amount of work in progress.

•Inspecting and Adapting the Workflow: Regularly reviewing and adjusting the workflow to improve efficiency and effectiveness

Little's Law states:

•Average Cycle Time = Average Work in Progress (WIP) / Average Throughput.

Little's Law is used to understand and forecast the performance of a workflow system. It implies that if you know two of these three variables (Cycle Time, WIP, Throughput), you can calculate the third. The correct formula is Option A(

Options B, C, and D do not correctly state Little's Law.

Supplementing Scrum with Kanban practices encourages team collaboration and swarming. Kanban practices such as visualizing the workflow, limiting WIP, and focusing on flow metrics foster an environment where team members are more likely to collaborate closely to resolve bottlenecks and ensure a steady flow of work. This collaboration, often called "swarming," involves team members working together on fewer items to complete them faster, thereby enhancing team dynamics and efficiency

An SLE of 85% for 5 days signifies that the team anticipates they will complete items within 5 days, 85% of the time. This helps set clear expectations with stakeholders, ensuring transparency around potential delivery timelines. The SLE is based on historical data and provides a probability-based forecast, rather than a commitment. References: The Kanban Guide for Scrum Teams​.

The Definition of Done (DoD) still applies even if policies are explicitly stated at each column of your workflow. The DoD is a fundamental concept in Scrum that ensures a shared understanding of what it means for work to be complete. Even with explicit policies at each stage of the workflow, the DoD provides a consistent standard for the team's deliverables, ensuring quality and alignment with stakeholder expectations

Limiting Work in Progress (WIP) is likely to increase rather than reduce collaboration within a Scrum Team. When WIP limits are enforced, team members are encouraged to "swarm" around fewer tasks, focusing on completing them together rather than starting new work. This promotes more collaborative behaviors, such as pairing or mob programming, to get work items done efficiently