In the previous posts, I discussed the tasks and the board in Kanban. In order to be productive, you must focus on one task at a time. Kanban facilitates this process and defines the term of partially done work.
Partially done work in Kanban is the number of tasks fulfilled at the same time. The number of such tasks is determined by the indicator of WIP Work-In-Progress or ongoing work.
The WIP parameters describe the whole amount of work, which is currently started.
In theory, it is possible to open many tasks. But if we want to perform 10 tasks at a time, we will have to face many obstacles. The main reason is the time loss when shifting from one task to another (change costs). In order to limit work, limit jumping from one task to another – it will automatically save you time. It will also improve your quality. Too many opened tasks at the same time reduce productivity. It is necessary to limit the tasks opened. The determination of the number of opened tasks helps in calculating this parameter.
If your project is to take the entire year and you will deliver tasks every week, you may determine your WIP as 3.
Is it necessary to specify a limit?
In order to complete a task in an appropriate manner, you have to focus on the target. Work limitation ensures concentration and it will accelerate the time for the fulfilment of requirements. Less partially done work leads to a faster work flow: the time for delivering a new product is shorter. The limitation of partially done work is one of the fundamental rules of Kanban. It does not mean that you should work less but that you should do fewer things at one time. The limitation of WIP will allow for faster performance of work.
WIP in software engineering
In software engineering, a partly done task depends on the stage: done or undone artefact. It is important here to define such an artefact. For me it is usually a case of usage. It may also be user’s story.
The WIP in the software engineering will, for instance, be:
- Incomplete description of the usage case
- User’s story during implementation
- Unperformed approval test
- Unsubmitted installation code
Too many tasks implemented at the same time means that our work is too slow. The quality of such work drops. Often, during the day, there is a need for shifting between two or three difficult tasks. The effect is that we lose time for the implementation of a new task, and we do not complete the existing tasks.
A solution here is limits in partially done work. What does this mean? It means that in a given moment it is forbidden to have more tasks than specified in the limit.
There are many ways to determine the WIP. But this WIP limit is usually better than the higher one, because the aim is to limit the number of things that we work on simultaneously as much as possible. Setting a too low WIP limit may result in stopping the process. When WIP is set at zero, then in the event of any problem, which imposes a temporary suspension of work, the entire work process is stopped. My experience demonstrates that the WIP must be adjusted in the first iterations.
On the other hand, when the WIP limit is too high, work will be unfruitful. There will be tasks opened which will not be fulfilled. Limits should not be imposed but they should be a result of discussions within the team and with interested parties, and a consensus is most recommended here.
Limits should ensure the smooth workflow of the process. This topic will be discussed in the next Kanban entry.