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articles:pdca-the_origin [2022/03/06 17:11] – [ISO Promotes PDCA] rrandallarticles:pdca-the_origin [2022/09/27 10:14] – [The Shewhart Cycle (1939)] rrandall
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 ====== PDCA - The Origin Myth ====== ====== PDCA - The Origin Myth ======
  
-The PDCA (plan–do–check–act) is an iterative design and management method used in business for the control and continuous improvement of processes and products. While the PDCA cycle/wheel is often attributed to W. Edwards Deming... or to a lesser extent, Walter A. Shewhart, neither Deming nor Shewhart created the PDCA cycle/wheel.+The PDCA (plan–do–check–act) is an iterative design and management method used in business for the control and continuous improvement of processes and products. While the PDCA cycle/wheel is often attributed to W. Edwards Deming... or to a lesser extent, Walter A. Shewhart, __neither__ Deming nor Shewhart created the PDCA cycle/wheel!
  
 Unfortunately, both of these men continue to be incorrectly attributed with the creation of the PDCA cycle/wheel through poorly researched articles and publications... which themselves are referenced and result in a perpetuation of this myth. Unfortunately, both of these men continue to be incorrectly attributed with the creation of the PDCA cycle/wheel through poorly researched articles and publications... which themselves are referenced and result in a perpetuation of this myth.
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 {{ :articles:shewhart-5_steps_in_the_operation_of_control.png?direct&600 |}} {{ :articles:shewhart-5_steps_in_the_operation_of_control.png?direct&600 |}}
  
-Upon reading the source materials, we recognize that it is quite a //stretch// to cite the PDCA as the same as the "Shewhart Cycle". Rather than a basis for continual/continuous improvement, Shewhart's "cycle" would be better described as a "closed-loop" self-correcting system intended to achieve "optimization" of a process +Upon reading the source materials, we recognize that it is quite a //stretch// to cite the PDCA as the same as the "Shewhart Cycle". Rather than a basis for continual/continuous improvement, Shewhart's "cycle" would be better described as a "closed-loop" self-correcting system intended to achieve "optimization" of a process __using a "Control Chart"__.
 ===== The Deming Cycle (1950) ===== ===== The Deming Cycle (1950) =====
-{{ :articles:1950_deming_cycle_transparent.png?direct&400|Deming Cycle introduced in 1950}}+{{ :articles:1950_deming_cycle_transparent.png?direct&350|Deming Cycle introduced in 1950}}
 Inspired by the "Shewhart Cycle", W. Edwards Deming created his own "Deming Cycle", which he introduced in 1950 at a [[http://juse.or.jp/english/|"Japanese Union of Scientists and Engineers" (JUSE)]] sponsored eight-day seminar on statistical quality control for managers and engineers. His straight-line: Step 1- "Design", Step 2 – "Produce", Step 3 - "Sell" was converted to a circle with a fourth step added: Step 4 - "Redesign through marketing research". Inspired by the "Shewhart Cycle", W. Edwards Deming created his own "Deming Cycle", which he introduced in 1950 at a [[http://juse.or.jp/english/|"Japanese Union of Scientists and Engineers" (JUSE)]] sponsored eight-day seminar on statistical quality control for managers and engineers. His straight-line: Step 1- "Design", Step 2 – "Produce", Step 3 - "Sell" was converted to a circle with a fourth step added: Step 4 - "Redesign through marketing research".
  
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 ===== The Deming PDSA Cycle (1986) ===== ===== The Deming PDSA Cycle (1986) =====
  
-In 1986, Deming reintroduced his "Deming Cycle" (which he stated was inspired by the iterative nature of the "Shewhart cycle"). He stated that the new PSDA Cycle came directly from the 1950 version. However, after reviewing the original "Deming Cycle", this new model is NOT the same. It appears that Deming was simply "going with the flow" since JUSE had credited him with the PDCA cycle, with a slight modification to improve it.+In 1986, Deming reintroduced his "Deming Cycle". He stated that the new PSDA Cycle came directly from the 1950 version. However, after reviewing the original "Deming Cycle", this new model is NOT the same. It appears that Deming was simply "going with the flow" since JUSE had credited him with the PDCA cycle, with a slight modification to improve it.
  
 {{ :articles:pdsa_cycle.jpeg?direct&400 |}} {{ :articles:pdsa_cycle.jpeg?direct&400 |}}
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 For a more detailed article on the history of PDCA / PDSA, read: {{ :articles:evolution_of_the_pdca_cycle.pdf |"Evolution of the PDCA Sysle"}}. For a more detailed article on the history of PDCA / PDSA, read: {{ :articles:evolution_of_the_pdca_cycle.pdf |"Evolution of the PDCA Sysle"}}.
  
-===== ISO Promotes PDCA =====+ ===== ISO Promotes PDCA =====
  
-Beginning with ISO 9001:2000, ISO began promoting what Deming called "//the corruption PDCA//". This continued in ISO 9001:2008. While this may have seemed like a good idea, in theory, its application was confusing to many uses... and auditors.+Beginning with ISO 9001:2000, ISO began promoting what Deming called "//the corruption PDCA//". This continued in ISO 9001:2008. While this may have seemed like a good idea, in theory, its application was confusing to many users... and auditors.
 {{ :articles:pdca_from_iso_9001_2008_transparent.png?direct&600 |}} {{ :articles:pdca_from_iso_9001_2008_transparent.png?direct&600 |}}
  
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 {{ :articles:pdca_from_iso_9001_2015_transparent.png?direct&600 |}} {{ :articles:pdca_from_iso_9001_2015_transparent.png?direct&600 |}}
  
-Worse, in an effort to address ISO 9001:2015 / AS9100:2016, sec. 4.4.1, some companies have used the above PDCA diagram in an effort to describe the sequence and interaction of their processes.+Worse, in an effort to address ISO 9001:2015 / AS9100:2016, sec. 4.4.1, some companies have used the above PDCA diagram (or variations/modifications of it) in an effort to describe the sequence and interaction of their processes.
  
-While ISO itself has not provided direct guidance as to whether this is acceptable, AS9100 uses ISO 9001 as a "base/foundation" by simply adding requirements to the ISO 9001 standard. An AS9100 user asked "//Is using the process diagram in Figure 2 from clause+While ISO itself has not provided direct guidance as to whether this approach is acceptable, AS9100 uses ISO 9001 as a "base/foundation" by simply adding requirements to the ISO 9001 standard. An AS9100 user asked "//Is using the process diagram in Figure 2 from clause
 0.3.2, in your quality manual for interaction between the processes sufficient?//". 0.3.2, in your quality manual for interaction between the processes sufficient?//".
  
-The official response was "//No//." Further explanation was provided stating: "//This diagram is not intended to define an organization’s processes and their interaction.//" And: "//In addition, Annex A.1 of the standard provides this statement: “The structure of clauses is intended to provide a coherent +The official [[https://iaqg.org/|IAQG]] response was "//No//." Further explanation was provided stating: "//This diagram is not intended to define an organization’s processes and their interaction.//" And "//In addition, Annex A.1 of the standard provides this statement: “The structure of clauses is intended to provide a coherent 
-presentation of requirements, rather than a model for documenting an organization.//"+presentation of requirements, rather than a model for documenting an organization".//"
 ===== Major PDCA / PDSA Cycle Obstacles ===== ===== Major PDCA / PDSA Cycle Obstacles =====
  
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 ===== A Better Alternative ===== ===== A Better Alternative =====
  
-Clearly, "continuous improvement" of any individual process has its limits. However, few companies reach that point where they're struggling to improve further. Ultimately, improvements take place in spurts.+Clearly, the "continuous improvement" of any individual process has its limits. However, while recognizing that improvements take place in spurts, I rarely see //significant// improvements taking place in ISO 9001 or AS9100 registered companies.
  
-Rather than use the PDCA model, a much better approach is to follow the DMAIC model (Define, Measure, Analyze, Improve and Control). As improvements are made, the PDCA cycle fails to address "Control" (sustainment) of the improvement... to ensure that the process doesn't revert to its previous condition.  +Rather than use the PDCA model, a much better approach is to follow the DMAIC model (Define, Measure, Analyze, Improve, and Control). As improvements are made, the PDCA cycle fails to address "Control" (sustainment) of the improvement... to ensure that the process doesn't revert to its previous condition.  
  
-As you move from one process to another, utilizing DMAIC, you can re-visit any of the processes previously improved to determine whether another DMAIC would be appropriate (for greater improvements).+As you move from one process to another, utilizing DMAIC, you can re-visit any of the processes previously improved to determine whether another DMAIC would be appropriate for further improvements.
  
 {{ :articles:dmaic-aug-2019-01.png?direct&800 |}} {{ :articles:dmaic-aug-2019-01.png?direct&800 |}}
  
-To further enhance the effectiveness of DMAIC, many users incorporate TRIZ into the Analyze & Improve portions of the DMAIC process.+To enhance the effectiveness of DMAIC, many users incorporate [[articles:triz_application|TRIZ]] into the Analyze & Improve portions of the DMAIC process.
  
-[{{  :articles:2048px-40_principles_of_triz_method_720dpi.jpeg?direct&800 |40 principles of TRIZ. Copyright By FotoSceptyk – Own work, CC BY-SA 4.0, \\  https://commons.wikimedia.org/w/index.php?curid=45719323  }}]