Why Design of Experiments Fails: The Gap Between Statistical Rigour and Process Reality
Most industrial DOE produces statistically valid results that solve the wrong problem. Here is how quality engineers systematically misuse the…
Six Sigma & Data
150 articles
Tolerance Stack-Up Analysis: The Engineering Discipline Your Production Line Depends On
When components pass inspection but assemblies fail, the root cause is rarely manufacturing variation. It is tolerance accumulation that was…
How Cost of Quality Reporting Normalises the Waste It Was Built to Eliminate
The COQ framework was designed to trigger prevention investment. Instead, most organisations use it to budget failure. Here is how…
How Six Sigma Became a Certification Factory
The DMAIC framework is sound. The belt industry it spawned is not. A field assessment of what went wrong and…
Statistical Process Control: Why Your Control Charts Lie and Your Process Drifts
Most SPC systems degenerate into compliance theatre. The control limits are frozen, the patterns are ignored, and the data is…
Measurement System Analysis: Why a Passing Gage R&R Study Means Nothing on the Factory Floor
A Gage R&R under 10% satisfies auditors but routinely fails operators. Here is why your MSA study is likely a…
The Hawthorne Effect in Manufacturing Quality: Recognising and Managing Observation Bias
Process audits, capability studies, and MSA results all distort when operators know they are being watched. Here is how to…
Regression to the Mean: How Manufacturing Quality Systems Reward Random Noise
Most celebrated corrective actions are statistical illusions. Recognising regression to the mean prevents your organisation from rewarding luck and punishing…
Diagnostic Design of Experiments: Reading Process Failures Before Running the Matrix
Most DOE initiatives fail before the first run because the diagnostic groundwork is skipped. A framework for evaluating whether your…
Acceptance Sampling Plans: The Statistical Illusion Inflating Your Quality Metrics
Most manufacturers use ISO 2859-1 AQL tables without understanding the operating characteristic curve. Here is what your sampling plan actually…