A colleague pointed to this Applying Theory of Constraints at Scale from the Lean Kanban United Kingdom conference in May 2015 (not 2019) by Tony Grout and Chris Matts from Microsoft’s Skype team.
Scale in this perspective is the Skype development team of ~2,000 developers across ten locations and just about every operating system (and many versions). The speakers made the comment that developing and testing for all these variations is challenging.
In their setup, they describe the many solutions they have tried from the full Theory of Constraints to Cost of Delay to Metrics to Staff Liquidity to Coaching and Agile. They discovered challenges and difficulties with all of these approaches and concepts, even though they make a lot of sense in and of themselves. They discovered with a number of these great concepts that they didn’t answer the real problem that the company was having - they often worked in small examples but that at scale they struggled to see the benefits. Sometimes the process of scaling uncovered unexpected negative side effects that derailed the efforts, like people misunderstanding “self-directed teams” as “managers have nothing to do.”
So what did work for them? Back to the drawing board, and they used Theory of Constraints and the 5 Focusing Steps*, starting with “Step 0: Define the Goal” - what are we trying to do?
Identify the constraint.
Decide how to exploit the constraint.
Subordinate everything else to the above decisions.
Elevate the constraint.
If the constraint has moved in any of the above steps, return to Step 1. Don’t let inertia become the constraint.
The speakers said that when they stepped back and asked where is the constraint (by understand what is the work and their capacity), they discovered the 20% of the teams that truly limit their ability to flow work through the system. (And another 20% of the teams that couldn’t get work done because they depend on the constrained 20%.) It gave the entire organization the ability to focus on the right things. This helped them see that simply adding capacity everywhere (step 4) wasn’t going help create more value - they needed to discover how to get the most out of the constraint and flow everything with respect to that.
Now they could bring in many of the other ideas, and they made sense when applied in the right ways. Identifying the constraint helped them see where the problems were, instead of giving them the specific directions on “fixing” the problems.
An example toward the end of the talk was instructive for the value of having a clear understanding of the constraint. A new CEO came in and changed direction - which changed what all the teams needed to work on. They were able to identify the constraint and re-direct the whole organization in weeks, rather than the expected six months.
* A small element that bothered me in the talk was the way the speakers described the five focusing steps as Identify the constraint, Prioritize the constraint, Optimize the constraint, Add to the constraint, Repeat. The middle three elements are very different from what I understand of the five focusing steps - and they could drive the wrong behaviors and understanding.