I’ve thought for some time now that WIP limits are a special form of explicit policy – one that is called out specifically because it is a core concept behind kanban systems. That has made be uncomfortable with the third Kanban Thinking heuristic; “Limit (with Policies)”. Limits and policies are a means to an end. What is that end (other than the over-arching goal of making in impact)? Further, all the other fuller versions of the heuristics are of the form “<verb> the <noun>”.
- Study the Context
- Share the Understanding
- Limit with Policies
- Sense the Capability
- Explore the Potential
We define WIP limits and explicit policies in order to create a boundary within which the system can evolve, and which allows self-organisation to happen. Thus they create a container for the system. That leads to the heuristic “Contain the Work”, which covers both WIP limits and explicit policies.
I also like the notion of containing rather that limiting for another more subtle reason. Limiting, to me, implies applying an external pressure in order to reduce WIP. I used to think this was a good thing, but now consider WIP limits to be an economic choice – too little WIP can have a negative impact if it leads to throughput becoming too low, or a portfolio with not enough variety. Containing, on the other hand, implies a different dynamic where we are trying to resist internal pressure in order to avoid WIP getting out of control.
This all might be semantics! I’d love to get feedback on this alternative to talking about limits. What does “contain the work” suggest to you? What other alternatives would you suggest?