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--- articles:whac-a-mole [2023/03/16 18:06] – [Conclusion] rrandall
+++ articles:whac-a-mole [2024/02/05 21:17] (current) – [The "Human Factors" in Cause & Effect Analysis] rrandall
@@ Line 13: / Line 13: @@
 |  **Assignable Cause**  | unusual / abnormal,\\ not previously observed,\\ non-quantifiable variation  |
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-The staff is well trained and rarely make these mistakes. If one were to initiate a "corrective action" to address this situation, it would quickly prove futile because there is __NO "assignable" root cause__ to be eliminated. This type of error is a normal, random (common cause) variation in the restaurant's process due to the volume of silverware that is washed, sorted, and manually rolled into napkins by the staff.
+The staff is well trained and rarely make these mistakes. If one were to initiate a "corrective action" to address this situation, it would quickly prove futile because there is __NO "assignable" cause__ to be eliminated. This type of error is a normal, random (common cause) variation in the restaurant's process due to the volume of silverware that is washed, sorted, and manually rolled into napkins by the staff.
 However, one night you arrive and order dinner only to find that the food takes much longer than normal to arrive at your table has been over-cooked and is cold. You complain to the server who apologizes explaining that their chef is unexpectedly absent tonight due to an illness. And that this was terrible timing because his Assistant chef is traveling on vacation. Consequently, a replacement chef, who is unfamiliar with both their kitchen and menu, had to be brought in to fill this temporary need.
-Unlike the silverware issue, this is an unusual/abnormal, situation that has not previously occurred. Therefore, this would be a “special cause” variation in their process __with an "assignable" root cause__. Special causes produce systematic effects/errors in a process.
+Unlike the silverware issue, this is an unusual/abnormal, situation that has not previously occurred. Therefore, this would be a “special cause” variation in their process __with an "assignable" cause__. Special causes produce systematic effects/errors in a process.
 The [[https://support.minitab.com/en-us/minitab/18/help-and-how-to/quality-and-process-improvement/control-charts/supporting-topics/basics/using-control-charts-to-detect-variation-in-a-process/|Minitab® 18 Support web site]] offers "**Examples of common-cause and special-cause variation**" in a table (provided below with a few minor improvements).
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 ==== Reactive Process Improvement ====
-In order to properly implement a "corrective action", there must be an assignable "root cause". And in order for there to be an assignable "root cause", the nonconforming condition must be the result of a "special cause" variation (i.e., an “unnatural pattern” in the process, which is unusual, not previously observed, non-quantifiable variation in the process).
+In order to properly implement a "corrective action", there must be an "assignable cause". And in order for there to be an "assignable cause", the nonconforming condition must be the result of a "special cause" variation (i.e., an “unnatural pattern” in the process, which is unusual, not previously observed, non-quantifiable variation in the process).
 Consequently, because "special causes" produce systematic effects/errors in a process, properly implemented "corrective actions" are __reactive__ process improvements... refining an existing process.
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 However, the “Zero Defects” concept didn’t gain widespread popularity until it was promoted by [[https://asq.org/about-asq/honorary-members/crosby|Philip B. Crosby]], in his book “//Quality is Free//” (1979). Crosby is credited with having developed the “Zero Defects” concept during the early ‘60s while working at the Martin Company as the quality control manager overseeing the Pershing missile program.
-This is diametrically opposed to the philosophy and teachings of W. Edwards Deming, who repeatedly showed that, no matter how vigilant the employees, every process contains inherent (i.e., natural “Common Cause”) variations resulting in defects. This was most popularly demonstrated through Deming’s “[[https://www.youtube.com/watch?v=ckBfbvOXDvU|Red Bead Experiment]]”. In fact, point 10 of [[https://deming.org/explore/fourteen-points/|Deming's 14 points]] specifically rejects the “Zero Defects” concept, stating: "//Eliminate slogans, exhortations, and targets for the work force asking for __zero defects__ and new levels of productivity. Such exhortations only create adversarial relationships, as the bulk of the causes of low quality and low productivity belong to the system and thus lie beyond the power of the work force//".
+This is diametrically opposed to the philosophy and teachings of W. Edwards Deming, who repeatedly showed that, no matter how vigilant the employees, every process contains inherent (i.e., natural “Common Cause”) variations resulting in defects. This was most popularly demonstrated through Deming’s “[[https://www.youtube.com/watch?v=ckBfbvOXDvU|Red Bead Experiment]]”. In fact, point 10 of [[https://deming.org/explore/fourteen-points/|Deming's 14 points]] specifically rejects the “Zero Defects” concept, stating: "//Eliminate slogans, exhortations, and targets for the work force asking for __zero defects__ and new levels of productivity. Such exhortations only create adversarial relationships, as the bulk of the causes of low quality and low productivity belong to the system and thus lie beyond the power of the workforce//".
+===== The "Human Factors" in Cause & Effect Analysis =====
+While we're on the topic of "Human Errors", these are very much prevalent in the Cause & Effect Chain Analysis process.
+First, the individual(s) performing the Cause & Effect Chain Analysis have their own bias for what the "cause(s)" should be. Like it or not, a "Blame Game" often occurs during this process. No individual or manager wants to be the target of that "negative" perception. So "finger pointing" often ensues.
+Another important "Human Factor" is that humans have evolved to "think" in a linear fashion. Consequently, people have difficulty making sense of non-linear events that have branches and/or parallel causes/effects. Read any Corrective Action Report and you will see a linear story detailing the events in a sequence... omitting any parallel causes/effects.
+Sadly, most Quality Professionals have not been taught that every event must have at least one condition and one action (i.e., "[[https://www.amazon.com/Apollo-Root-Cause-Analysis-Thinking/dp/1883677114|Apollo Root Cause Analysis]]"). Similarly, most Quality Professionals have also not been taught that upon identifying a "Cause - Effect" relationship, the "Effect" now becomes the "Cause" for the next step in the analysis. In other words, whether something is a "Cause" or "Effect" depends upon the analyst's perspective.
+Also, the simple "5 Whys" method only goes to the point of the analyst's "ignorance"... NOT the mythical "Root Cause". In other words, the analyst asks "Why?" until he cannot answer the question. Out of ideas, he assumes that is the "Root Cause"... when in reality, the analyst(s) has merely reached their "Point of Ignorance". While the analyst could continue the analysis by obtaining participation from one or more people (Subject Matter Experts) who can answer that question, they too would eventually encounter their "Point of Ignorance".
+Consequently, the "5 Whys" method leads to untrained analysts ignoring multiple links in the cause-and-effect chain... many of which would prevent the recurrence of the nonconformity.
 ===== Conclusion =====
-Upon understanding “Common Cause” and “Assignable Cause” variations in a process, one soon realizes that these are both associated with "risk management". And one of the most popular tools used for addressing quality-related risk is the [[https://asq.org/quality-resources/fmea|"Failure Mode and Effects Analysis" (FMEA)]]... or FMECA ("Failure Mode, Effects and Criticality Analysis"). The FMEA & FMECA are used for managing risks related to a single event project or design. A "Risk Register" (sometimes with a graphical "Risk Matrix") is more appropriate for addressing ongoing process risks.
+Upon understanding “Common Cause” and “Assignable Cause” variations in a process, one soon realizes that these are both associated with "risk management". And the most popular tools used for addressing quality-related risk is the: \\
+  * [[https://asq.org/quality-resources/fmea|"Failure Mode and Effects Analysis" (FMEA)]]... or FMECA ("Failure Mode, Effects and  Criticality Analysis"), and
+  * "Risk Register" (sometimes with a graphical "Risk Matrix")
+The FMEA & FMECA are used for managing risks related to a single event project or design. A "Risk Register" is used (and maintained) for addressing ongoing process risks. Sometimes, Project Managers will use a "Risk Register" for a long-term project so as to address updated risk mitigation controls.
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+Some people have attempted to apply the single event FMEA to ongoing processes by simply renaming it "Process Failure Mode and Effects Analysis" (PFMEA). This doesn't work because the FMEA is designed for a single-event project or design. In contrast, a "Risk Register" is "maintained" through continuous updates as improvements are made to the process.
+</WRAP>
-IF a nonconformity is due to a “Common Cause” variation, then "controls" can be put in place to "__mitigate__" the risk of the nonconformity recurring. However, IF a nonconformity is due to an "Assignable Cause" variation, then the process can be changed to "__eliminate__" the cause of the nonconformity recurring (i.e., reducing the probability OR impact of a risk to zero).
+IF a nonconformity is due to a “Common Cause” variation, then "controls" can be put in place to "__mitigate__" the risk of the nonconformity recurring. However, IF a nonconformity is due to an "Assignable Cause" variation, then the process could possibly be changed to "__eliminate__" the cause of the nonconformity recurring (i.e., reducing the probability OR impact of a risk to zero).
-Upon completing a PFMEA ("Process Failure Mode and Effects Analysis"), one quickly realizes just how few "true" corrective actions are actually possible. And that by shifting the mindset to "risk management", rather than being obsessed with "risk elimination" (aka "Corrective Action"), significant quality improvements can finally be realized.
+Upon completing an FMEA/FMECA or Risk Register, one quickly realizes just how few "true" corrective actions are actually possible. And that by shifting the mindset to "risk management", rather than being obsessed with "risk elimination" (aka "Corrective Action"), significant quality improvements can finally be realized.