Kanban: When is it appropriate? (part 1)
In the Kanban Coaching Professional Masterclass, I teach coaches and those leading Kanban initiatives how to assess the appropriateness of the Kanban Method and the appropriateness of applying a kanban system within an organization. This is the first of a series of blog posts on appropriateness and getting started with an enterprise scale Kanban initiative.
Appropriateness of Using a Kanban System
When should we use a kanban pull system? Firstly, we should realize that we apply kanban systems to a service delivery workflow. Assuming we have identified a workflow and can describe the types of work it processes and the service interface and service levels it offers then we have a good candidate for a kanban system. Early examples included IT system software maintenance and sustained (or business as usual) engineering. This is classic example of an IT service within most large corporates. So we have a service delivery workflow but why would we choose to use a kanban system with such a workflow?
There are various reasons for choosing a kanban system. Any or all of these might be true and would represent an appropriate choice:
- Deferred commitment is desirable – because early commitment is causing excessive re-work and wasted effort
- There is unnevenness in the flow of work – and we want smooth, even flow
- The workflow system (and its workers) are overburdened – and we wish to relieve this
Let’s look at each of these in turn and learn how to recognize them
Deferred Commitment is Desirable
We prefer to defer commitment on specific work items to be processed through a service delivery workflow if the future is uncertain and our opinion on what is important and timely is likely to change. Similarly if priorities keep changing and we are continually re-planning and communicating new delivery dates and new sequencing for items to be processed in through the service, we would prefer to defer commitment and reduce our planning and prioritization overhead. If we do this properly, we can reduce waste in this area to almost zero. We would also prefer to defer commitment if we have a high abondonment rate – ideas that are never started and always depioritized – or a high discard rate – ideas that we actively discard as of low value, low return on investment, or low priority. Equally, if we have a high abort rate after commitment where we actively cancel items that had been requested and confirmed, or if we have a high level of completed work which is delivered by never used or not actively commissioned for use in the field. All of this indicates that we have a habit of committing early to things for which we are not certain we really want to take delivery. This is a strong indicator that we wish to defer commitment. Kanban systems enable us to defer commitment and would be an appropriate choice. In summary, deferred commitment is desirable when
- the future is uncertain
- things might change
- priorities are often changing
- replanning is common and frequent
- there is a high abandonment rate for incoming requests
- there is a high discard rate for incoming requests
- there is a high abort rate for committed requests where work already started
- there is a high level of delivered work which is ignored, never used or never commissioned for use in the field
Unevenness in the Flow of Work
Typically unevenness in the flow of work affects our predictability or has a tendency to overburden workers then leave them idle for periods of time. If we value predictability or we value evenly loaded workers who work to produce good quality then we wish to smooth the flow of work through the service. Unnevenness in flow can be caused by large batch transfers, by arrival of unplanned work in an unpredictable fashion, or by blocking issues which prevent work from being completed. Unplanned work is often of a speculative nature and often comes with a desire for a high class of service. This results in planned work being set aside in order to service the unplanned, speculative work. Requests for information such as estimates for future work are typical of unplanned, unpredictable, speculative demand. The arrival of this work prevents planned and committed work from being delivered in a timely manner and within customer expectations and service level agreements.
In summary, unevenness in flow is caused by
- large batch transfers
- unplanned, speculative, disruptive work requests
- blocking issues
Overburdening
It is common in creative and knowledge worker industries for workers to be constantly overburdened with too many requests and too much work-in-progress. The results of this lead to stressed workers, poor quality and long and unpredictable lead times. If we desire good quality, short lead times and predictable delivery then we need to relieve the workers from overburdening. This is simply achieved with a WIP limit. Kanban systems are good solutions for relieving overburdening.
In summary, overburdening can be observed by
- long queues of requests waiting to be serviced
- too much work-in-progress
- too much multi-tasking and task switching
- stressed workers
- poor quality
- long and unpredictable lead times
Summary
Kanban systems are an appropriate choice for improving service delivery when there is a need for greater predictability in delivery times, higher quality in deliverables, deferred commitment would reduce waste and re-work in planning and prioritization, there is a need to smooth the flow of work through the service, the system (and its workers) are overburdened leading to poor quality and long, unpredictable delivery times.
The use of kanban systems can: save money by reducing wasteful upstream activities such as planning and prioritization; improve ultilization by smoothing the flow of work; improve service delivery by improving quality, predictability and time to delivery.
