drmike's blog

Neil always used to confound and shock me. He was always pursuing perfection. And I would always retort something like, “But, the real world isn’t perfect.”

Over the years, I slowly realized the value and wisdom of Neil’s mindset. It is consistent with traditional lean thinking (as long as it does not paralyze the PDCA cycle), and it helps drive innovation and the right thought process. I have found that lean thinkers not only benchmark themselves against the competition, they also benchmark themselves against perfection. This is where math can help.

Combinations and Permutations How many different poker hands are there? How many different pizza orders can be made? How many different ways can this work schedule be filled out? How many different ways are there to arrange your books in a bookshelf? These are all examples of combinations and permutations. And knowing how to calculate them is a helpful tool for decision making.  The basic equations are: .

Life happens. Sometimes it rains on wedding days. Sometimes a supplier misses a ship date, and sometimes there are glitches in our processes. The challenge for lean practitioners is what to do about this – especially since all of these things could happen.

Did first-class passengers on the Titanic get preferential treatment during the evacuation? James Cameron’s movie certainly seems to suggest so, but let’s look at the data.

Flow is a key lean principle. We should relentlessly pursue a state in which value flows smoothly, without interruption to the customer. But how can this be achieved? Assuming that we have adequate system stability, repeatability, and other important "ilities," as well as a design and culture that facilitates continuous flow (admittedly, really difficult stuff), the answer is amazingly simple – match capacity to demand. So, if you have 10 customer requests your capacity should be 10 customer requests, and if the demand is 1,172 customer requests the capacity should be 1,172 requests.