The Gravity of PDCA

How the scientific method can turn a daily habit into a quality tool

by T. Dan Nelson

The law of gravity doesn’t depend on humanity’s understanding of it to have an effect. Humans knew how to interact with gravity—to an extent—far before Sir Isaac Newton "discovered" it.

Likewise, the principles of quality management didn’t arrive with ISO 9001. Successful organizations understood these basic principles long before the first standard was published.

Before Newton, people understood the effects of gravity enough to successfully shoot an arrow, but they were unable to elicit gravity in abstract concepts because there was no empirical method behind it.

Newton’s work with gravity allowed us to develop a scientific understanding of this natural phenomenon by systemically developing hypotheses, and observing, measuring, testing, and reformulating these hypotheses until their explanatory powers were satisfactory. The resulting scientific understanding increased people’s abilities to function in this universe.

The science behind PDCA

Plan-do-check-act (PDCA) represents an intersection between the scientific method and everyday operations. Given an objective, whatever process is defined to achieve that objective can be—and often unknowingly is—subject to PDCA.

In an ideal situation, as soon as an idea to achieve an objective is considered, a plan is conceptualized to follow through on that idea. After a plan seems robust enough to account for all potential risks in achieving the objective, the plan is implemented.

The method seems basic, but it can be easy to skip or skim over steps if the logic behind each is not properly understood. That is why it is important for quality professionals to understand that PDCA is rooted in the scientific method—a sound approach to reaching the best possible conclusion.

Hypothesis: After recognizing an opportunity for improvement, the plan put in place to take advantage of this opportunity represents the hypothesis.

Similar to forming the best hypothesis for a scientific experiment, it is important to consider all available data when formulating a plan.

Test: Carrying out the plan correlates to the testing or experimental phase of the scientific method. Organizations implement their plans akin to a scientist observing and measuring nature to test a hypothesis.

Analyze: After completing testing, organizations check results to determine whether they are acceptable.

If more improvement is needed, it is the same as a scientist finding a false hypothesis. The organization must go back to the hypothesis (plan) stage and use the additional data gathered from the first test to create a new plan and retest it.

Report: If the results are perfect, an organization should report this conclusion by standardizing the process. This is the final "act" stage of PDCA.

While some quality tools can seem abstract or unnecessary from the surface, explaining the logic behind them helps get employees on board with improvement plans. It is up to top management to take ownership of these improvement procedures to ensure all steps are being taken and only acceptable results are standardized. Otherwise, the same results can be expected.

T. Dan Nelson is principal at T. D. Nelson Consulting in Groton, NY. He has an MBA from the University of Iowa in Iowa City.

Totally agree and thought similar as you.
--Aaron, 12-04-2017

After digging deep into the contents of the article, I�m convinced that there�s science and logic behind the plan-do-check-act (PDCA) cycle. Using PDCA is similar to conducting scientific research and proving the theory behind it. Whether we label it or not, we are using it in our daily lives, but not always in a conscious way. This is a good article worth reading.
--Nayel Altarawneh , 04-04-2017

Dear Dan,
The example with law of gravity I consider so appropriate!
Each of us daily we apply the PDCA cycle in real life, regardless if we know the its name and scholastic theory, or we have not any idea that all taken steps are covered by this name.
By reading this article it is possible in a very easy manner to convince those persons who still need this, that themselves use many of the tools and approaches of Quality Management in their quotidian life even without "labeling" it appropriately.
All the best,
Catalina Tutulea

--Catalina Tutulea, 01-05-2017

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