Embrace Change but Keep Costs Visible
"What happens when we're at our WIP limit and 'do it now' work crops up?"
If you've structured your process with spare capacity, rather than striving for 100% utilization, some Kanban processes allow for a special high-priority queue (sometimes called a "silver bullet") with a WIP limit of 1.
Some slack is essential for any lean or agile process, but special high-priority queues require even more. If an organization wants to reserve extra capacity, then this represents an ongoing cost to the business. It may be an acceptable cost, but it is never free.
More generally, though, the correct response is:
- Determine why the business expects "do it now" work to crop up on a regular basis. Expecting routine interruptions is a process smell that indicates that not everyone is on board with a queued workflow, or that key policies and processes have not been properly defined.
- When genuine emergencies do arise (and they do!), then it should be a jarring event to handle it. The goal of Kanban (or any other agile methodology) isn't to prevent important work from being done. The intent is to make the cost of new or unplanned work fully visible.
- The business (not individual stakeholders) should make a strategic decision about whether the opportunity cost of not doing something right now is higher or lower than the costs associated with lost work, unplanned change, or disruptions to flow. Costs can't be swept under the rug, but the business still has the ability to pay for the strategic decisions they make.
- When work exceeds capacity (not just an arbitrary WIP limit), then capacity must be shifted from one work product to another. There's no free lunch here. If your team is at capacity, then adding new work to the current cycle means something else must be removed or left undone.
In short, you can't create capacity out of thin air. Change has a cost. Kanban, Scrum, and others make these costs visible to the organization. It is then senior leadership's responsibility to make decisions about what costs to bear, and what "do it now!" things aren't really emergencies after all. It's amazing how well things can be prioritized when it's clear that they cost time or money, and that they were never really "free" in the first place.