PSK-I Questions and Answers

Scrum Teams using Kanban can start to increase predictability by reducing the amount of work in progress (WIP) through WIP limits. This approach helps to limit the number of items being worked on at any given time, thus reducing multitasking and context switching. It allows the team to focus on completing a few items before starting new ones, which directly impacts the flow of work and helps to predict when items will be completed. By controlling the WIP, teams can achieve a steady flow of work, improve cycle times, and make more reliable forecasts about future deliveries

According to the Kanban Guide for Scrum Teams, Work in Progress (WIP) limits are set to control the amount of work in progress in a system, enhancing flow, reducing bottlenecks, and ensuring smoother delivery. WIP limits can be changed as a result of an inspection and adaptation cycle, which primarily occurs during the Sprint Retrospective.

During the Sprint Retrospective, the Scrum Team reflects on its process, practices, and interactions. This is the time when the team inspects its flow, evaluates the effectiveness of the current WIP limits, and can make decisions to adjust them based on observed issues or potential improvements. The goal is to optimize the team's ability to deliver value, and adjusting WIP limits during the Retrospective allows for thoughtful consideration based on the team's experience and data from the completed Sprint.

Changing WIP limits at other times could disrupt the flow and reduce the predictability and stability that the limits are intended to create. Therefore, the best practice is to evaluate and change them during the Sprint Retrospective, where the team can inspect the results of their workflow and make informed decisions for the upcoming Sprints

By limiting WIP, Scrum Teams using Kanban create a more predictable flow, as it prevents the team from overcommitting and encourages them to finish work items before starting new ones. This aligns with Kanban’s principle of optimizing flow and Scrum’s iterative delivery approach. References: The Kanban Guide for Scrum Teams​​.

Kanban emphasizes explicit policies for better transparency and alignment, and elements such as the Definition of Done, Definition of Ready, and Product Backlog refinement can be utilized as explicit policies to clarify the Scrum Team’s working agreements. These policies help the team make consistent decisions and streamline their processes. References: The Kanban Guide for Scrum Teams and The Scrum Guide​​.

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

When Developers reserve capacity for unplanned work during a Sprint, the Sprint Goal becomes even more crucial. It serves as the guiding objective that aligns the team's focus amidst uncertainties or when unplanned work is introduced. By having a clear Sprint Goal, the Developers can ensure that any new items brought into the Sprint Backlog still align with the overarching objective of the Sprint, helping them maintain focus and coherence in their efforts throughout the Sprint

Lagging indicator metrics are metrics that provide information about past performance:

1.Velocity (Option A): This is a measure of the amount of work a Scrum Team completes in a Sprint. It is a lagging indicator because it reflects what has been done rather than predicting future performance.

2.Cycle Time (Option B): This metric measures the time taken to complete a work item from start to finish. It is a lagging indicator because it provides data on how long work items took to complete in the past.

3.Throughput (Option D): This refers to the number of work items completed in a given period. Like Velocity, it reflects past performance and is considered a lagging indicator.

Work in Progress (Option C) and Work Item Aging (Option E) are not lagging indicators:

•Work in Progress (C): is a current state metric that indicates how much work is currently in progress.

•Work Item Aging (E): is a leading indicator, providing insights into how long a work item has been in progress, helping predict delays or bottlenecks

Supplementing Scrum with Kanban practices can bring several benefits to a Scrum Team:

•Greater Collaboration (A): By using Kanban practices like visualizing work and managing flow, team members have clearer visibility into each other's tasks, fostering better collaboration.

•Reduced Average Cycle Time (C): Kanban's focus on flow and limiting WIP helps decrease the time it takes for items to move from start to finish.

•Better Transparency (D): Kanban practices enhance visibility into the current state of work, making it easier to identify bottlenecks and areas for improvement.

•Discover Areas of Variability (E): The use of flow metrics such as cycle time and throughput in Kanban can help identify variability in processes, enabling the team to make adjustments for more predictable delivery

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

Although WIP limits are central to Kanban, enhancing visualization and communication through Kanban boards can be a way to ease into WIP limits gradually. This alternative fosters transparency and alignment without directly imposing WIP constraints, which can be beneficial for teams adjusting to Kanban practices. 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

Reducing batch size does not always guarantee an increase in overall efficiency. While smaller batch sizes can lead to faster feedback, more frequent deliveries, and reduced risk, there can be situations where reducing the batch size too much results in inefficiencies, such as increased overhead costs or excessive context switching. Thus, the relationship between batch size and efficiency depends on the context, system constraints, and the nature of the work

The essential flow metrics for Scrum Teams utilizing Kanban are:

Throughput: Measures the number of items completed within a time period.

Lead Time: Time from when an item enters the system to when it exits.

Cycle Time: Time it takes to complete a work item once it starts.

Work in Progress (WIP): The number of items currently in progress but not completed.

These metrics are foundational in understanding and optimizing flow within Kanban systems used alongside Scrum​​. "Work Item Age" and "Cumulative Flow Diagram (CFD)" are useful metrics but are not listed as primary flow metrics in Kanban for Scrum Teams.

Adjusting WIP limits can directly impact Cycle Time and overall flow by reducing bottlenecks and increasing focus. Lowering WIP can enhance the team’s ability to complete work within a Sprint by minimizing task switching and promoting faster delivery of value. References: The Kanban Guide for Scrum Teams​​.