What is Kanban Pull System? A detailed Explanation

Kanban is one of the project management methodologies under the Agile Framework. It mainly focuses on the continuous delivery of the project rather than delivering the project at the end of the sprint. Also, it follows a visual approach in which tasks are managed and executed using visual cards. All these visual cards are managed using a digital board called the Kanban Board. Thus, it allows the teams to practice the agile principles of project management with a more adaptive and dynamic workflow.

What is a Kanban Pull System?

A Kanban pull-system approach is a demand-centric approach in which the project tasks are taken into progress when there is an actual need for it.

• Originally, the pull-system approach was derived from the lean manufacturing technique, in which the supply of materials or production is planned only when there is an actual demand from the customer side.
• In Kanban Project Management, the pull-system approach focuses on maintaining the tasks in the backlog feature and pulling them into the current workflow when the team capacity allows them or when there is a need for those tasks.

How does Kanban Promote a Pull-System Approach?

Kanban’s pull system is one of the great ways to practice the Agile Principles that help the users to track and reduce waiting time along with preventing team burnout. Thus, the team takes up the work only as much as they can manage. Generally, there are four main steps through which Kanban promotes the Pull system Approach namely. They are workflow visualization, WIP Limits, the Pull System, and finally, the implementation of the Pull Signals.

1. Visual Workflow

In Kanban, the project is broken down into smaller processes that contain multiple tasks. These multiple tasks are visualized in the Kanban board using the columns and swimlanes. Each task contains essential information such as the assignee, task type and deadline. These tasks are moved from left to right on the board according to the progress of the project.

We can also relate workflow visualization to a term called ‘Value Stream Mapping,’ which is a Lean Manufacturing technique to analyze and manage the flow of materials. However, in the Kanban, the "Value Stream Mapping" outlines the definition of various processes, their states and their transition throughout the project lifecycle. So, the Pull System starts with the identification of the process flow.

2. Work-In-Limit Progress

The project team has a particular capacity to take the tasks under execution and, your work will get stuck if there are too many tasks, more than the team’s capacity. Thus, Kanban allows us to limit the number of tasks in each column so that the team can manage the work according to their capacity.

In addition to this, WIP Limits also reduce the risks of task switching which happens when there are a lot many tasks to do in the project. Team members switch from one task to another to meet deadlines but indeed, they end up with a complex workflow. Hence, WIP helps them in preventing this.

3. Pull System

Kanban’s Pull System can be observed in two ways. First, the tasks are moved into the various processes from left to right in the Kanban board. For example, swimlanes containing the task or issues can move between the columns, from ‘To-do’ to ‘In-progress’ and finally to ‘Done.’ Another form of Pull System is between the backlog list and the Kanban board. Backlog maintains the upcoming tasks that are pulled into the Kanban board when they are needed or when team capacity allows them.

Both these scenarios form Kanban’s Pull System approach in which the primary goal is to take up the task only when there is a requirement. This approach is similar to the old Kanban technique that is used in Manufacturing systems to supply and produce only whenever market demand occurs. This helps reduce waste and increase resource utilization.

4. Applying the Pull Signals

Pull Signals are the triggers that tell us that the number of tasks in the column is less than the WIP limit. Therefore, more tasks can be pulled into the workflow. The pull signal can be applied to the previous column to indicate that the task can move further. Along with this, it can also be applied to pull tasks from the backlog when they are required.

One important use of the pull signals is to handle the dependencies among the various subtasks. If the execution of a task requires another task to be completed first, we can easily apply the pull signals for the task in the backlog. Also, we can ensure that no task remains neglected. Thus, the approach to handling the dependency becomes structured and efficient.

Difference between Pull-System Approach and Push-System Approach

Advantages of Pull System Approach

• Easy Prediction: The Pull System approach focuses on the quality of the tasks rather than quantity. Since there are lesser number of tasks, we can easily predict the completion time of the tasks. Along with this, there are shorter lead times in the project execution.
• Reducing Unnecessary Tasks: The Pull System approach reduces the unnecessary tasks in the workflow. This not only optimizes the workflow but saves the cost associated with maintaining the tasks that are not required.
• Utilization of Resources: The Pull System approach enables the agile teams to utilize the resources in a better way as there is neither overallocation nor under-allocation of project resources for tasks.

Disadvantages of Pull System Approach

• Inefficient for large projects: You may find it difficult to manage a complex project. The Pull System approach can become inefficient for large complex projects with a huge number of tasks that require parallel execution.
• Does not allow immediate changes: Since tasks are systematically pulled into the workflow, the Pull System approach does not allow us to easily execute the immediate tasks.
• Requires a skilled team: For properly implementing Kanban’s Pull System approach, a skilled team is required. Thus, the Pull System approach is not easy for the less skilled project professionals.

Conclusion

Kanban’s pull-system approach to work focuses on keeping the relevant and required tasks under execution and keeping the irrelevant things away from our project. Therefore, you can achieve the project targets in a shorter time by allowing the tasks to flow between the business processes in the pull System.