THE MEANING OF QUALITY

Good Quality means "On target with Minimum Variance". The single tool to manage Quality is the Process Behavior Chart (control chart). It is the only way to ensure your process will produce good Quality now and into the future. A deep understanding of variation is essential.

150 years ago, the meaning of quality was "good" vs "bad". Parts either conformed to specification or they didn't. The single essential tool was the go/no-go gauge. Most companies are still living in this era.

FORD
In the famous Ford transmission study almost 50 years ago, Ford engineers were blown away by the quality of Mazda parts. Not only did parts conform to specification but they had incredibly little variation. The Japanese had learned the meaning of Quality from Professor Deming in the 50's.

Ford failed to learn the meaning of Quality. They dived into the Six Sigma fiasco and kept counting defects. Six Sigma gave them plenty of defects to count. A long term study over hundreds of Six Sigma projects, showed 1 in 5 parts was defective AFTER "improvement" in "successful" projects.

SIGMA LEVELS
If you are calculating sigma levels, you do not understand the meaning of Quality. Sigma levels are based on defect counts, adjusted by a nonsense number based on a self confessed con man's fraud.

OEE
If you are calculating OEE, you do not understand the meaning of Quality. OEE is a nonsense number using the 150 year old version of quality.

NORMALITY
If you are testing your data for normality, you do not understand Process Behavior Charts. Process Behavior Charts work for ANY data distribution.

PROBABILITY
Process Behavior Charts are NOT probability charts. If you see any mention of probability such as "99.7%" you do not understand Process Behavior Charts.

BAD DATA
Process Behavior Charts do NOT depend on error free data. "We All Have to Use Less Than Perfect Data": Dr Wheeler: https://lnkd.in/dMRdbbX5

OTHER TOOLS
What about other tools like Run Charts? Run charts are ideal for detecting trends in non homogeneous processes, such as Covid data. For such data, Process Behavior Charts should never be used. An understanding of variation is essential.

LEARNING
Quality as a science started with Professor Deming, who integrated Dr Shewhart's charts and Professor Lewis' philosophy of quality. With each successive iteration thereafter, through Six Sigma, Lean, Quality 4.0 and 5.0, the meaning and importance of Quality has been lost.

The best way to learn the meaning of Quality is to read Dr Wheeler and Professor Deming's books. Our free Deming Funnel in Augmented Reality app, will also help you along the road to understand variation and the meaning of Quality.

   by Dr Tony Burns BE (Hon 1) PhD (Chem Eng)

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