CYCLE TIME VANITY!
Most people will take it for granted that if we perform work in less time, it must be better. Right?
All the mainstream approaches - #SAFe, #Scrum, #Kanban, #DevOps - obsessively insist that reducing Cycle Time is a Good Thing(tm)!
Or is it?
We primed ourselves to be open to what is not self-evident from the outset, but obvious hind sight.
We used the Story of the Egg of Columbus to get this idea across.
Deeper knowledge will afford us non-conventional thinking.
twitter.com/tendon/status/1523949167587905536
It's like the proverbial two sided coin.
It is not only about finding counter-intuitive solutions to our problems.
It is also to be ready to question what appear to be obvious solutions to well known problems.
Cycle Time reduction is of this nature.
Who in their right mind would ever question that reducing Cycle Time would not be a good thing?
(Besides, "Cycle Time" is the time from start to finish of an activity. In TameFlow I prefer to use the term "Flow Time" - but stick to "Cycle Time" here because of familiarity.)
Let's consider this thought experiment (another MENTAL MODEL).
An activity typically takes 10 days to perform.
There are two improvement proposals.
One will reduce the time to 9 days.
The other will increase it to 11 days.
Which do you pick?
No brainer! Right?
The 9 days solution!
Only a madman would go from 10 to 11 days.
This other proposal is even _increasing_ Cycle Time.
Of course it must be discarded!
But let's have some additional information.
The original activity of 10 days is broken down into three sub-activities taking respectively 3, 5, and 2 days (total 10).
First proposal changes to: 2, 5, and 2 (total 9).
Second proposal changes that to: 3, 4 and 4 (total 11).
The slowest activity was 5 days. It is the WORK PROCESS CONSTRAINT. It limits what the entire process can deliver.
The first proposal leaves the second step unchanged.
The second proposal reduces the second step from 5 to 4 days.
So the original process will have an effective OPERATIONAL THROUGHPUT of 1 item every 5 days; or 0.2 items per day.
The first proposal - despite the overall reduction in cycle time from 10 to 9, will still deliver 0.2 items per day.
So it really brings no improvement at all!
The second proposal reduces the second step from 5 to 4 days.
So the second proposal, despite the **overall increase in cycle time** from 10 to 11, will deliver 1 item every 4 days; or 0.25 items per day.
Conclusion:
First proposal with 10% cycle time reduction has zero impact on performance!
Second proposal with a 10% increase on cycle time will produce a 25% increase in performance: from 0.2 to 0.25 items per day.
Unbelievable!
Moral of this story.
Don't mindlessly pursue cycle time reduction.
Most of the time, the effort is vain.
And if you celebrate the gain, you are celebrating a vanity metric!
The only way to improve is to reduce the FLOW TIME of the WORK PROCESS CONSTRAINT.
This also explains, yet again, how operational performance improvements that might be celebrated as victories, at the end of the day delivery zero impact; yet the company sustains the cost of change, for a total loss!
The only improvement that matters is on the Constraint!
Did you enjoy this mind-boggling example?
It is taken out of Chapter 5, "Where to Focus Improvement Efforts" from "The Book of TameFlow".
leanpub.com/tameflow
Steve Tendon
@tendon
I help executives achieve superior financial, operational, organizational and human performance by adopting the power of Flow@Scale™.
