The major disadvantages of PDCA methodologies include oversimplification, confusion in acronym, an inherent reactive nature, and its ignorance of the 'people' element.
Oversimplification of the Improvement Process.
Walter Shewhart’s initial concept of plan-do-check-act (PDCA) was an adaptation of the Japanese way of improving a singe-workstation tight-loop production process through process control using continuous measurement and statistical control techniques.
This Japanese adaptation, which remains the core of the PDCA methodology, has serious drawbacks and gives rise to problems with PDCA.
- Shewhart’s adoption was a simplified abstraction of the original Japanese model, with the Japanese version remaining more detailed than Shewhart’s model. Shewhart’s version does not reflect activities such as sponsorship, leadership, coordination, communication, education, benchmarking, and establishment of the modified process required for successful improvement activities.
- Shewhart’s work in 1920 took place when the Japanese were not very conversant in English and vice versa. The adaptation from Japanese, for that reason, incorporates several flaws and vagueness. W. Edward Deming ironed out many flaws in the 1950s, but some miscommunication remains, especially the approach to the concept based on cultural background.
- The Japanese used PDCA for small-scale incremental improvements, whereas the present adaptation uses PDCA as the driver of large-scale complex changes
Confusion in the Acronym
The popularity of plan-do-check-act notwithstanding, the acronym of PDCA creates confusion because “Do” and “Act” have the same meaning in English.
The Compact Oxford dictionary defines “Do” as
- Perform or carry out (an action).
- Achieve or complete (a specified target).
- Act or progress in a specified way.
- Work on (something) to bring it to a required state.
The Compact Oxford dictionary defines “Act” as
- Take action; do something.
- Take effect or have a particular effect.
- Behave in a specified way.
The difference in scope of “Do” and “Act” remains confusing for the ordinary uninformed person. The correct word for “Act” is actually “Improve.”
Similarly, “Plan” has a limited range of meaning linguistically. The Compact Oxford dictionary defines “Plan” as
- A detailed proposal for doing or achieving something.
- An intention or decision about what one is going to do.
Shewhart’s and Deming’s PDCA includes aspects in the "Plan" phase such as creative or innovative thinking and handling complex adaptive systems, outside what one normally associates with planning, again causing confusion to the uninformed.
A major disadvantage of PDCA methodologies is its inherently reactive nature.
Although PDCA has a circular paradigm, it assumes that everything starts with Planning. This need not always be the case in real-life situations, where at times changing the rigid circular order might deliver better results.
The basic philosophy of PDCA is planning and undertaking an activity first and responding to the drawbacks after implementation. PDCA tries to correct rather than pre-empt mistakes, and does not encourage innovation or “out-of-the-box thinking” after the initial planning phase.
All these make PDCA inherently reactive in nature, unsuited to the highly competitive contemporary business environment that demands proactive thinking and action.
Ignorance of the "People" Element
Another major PDCA drawback is PDCA and change fatigue.
PDCA espouses the cause of continuous improvement. While this helps eliminate mistakes, improve productivity, and does away with complacency, continuous improvement entails continuous change--so the organization remains in a continuous state of flux. People having to adjust to change on a continuous basis and work in an uncertain environment encounter "change fatigue" or disenchantment, leading to several problems.
People become confused about the status of processes and procedures.
- Some people left out of the loop or unable to keep pace with the change continue following outmoded practices when others adopt the changed practice, leading to organizational dysfunction.
The success of any process or intervention depends on how the people involved accept the same. PDCA assumes that people will use the cycle and make things happen and makes no effort to include people. A good change management process needs to cover people, process, and product. While PDCA looks into the product and process, it ignores the people component of change.
- American Society for Quality. Plan–Do–Check–Act Cycle: http://www.asq.org/learn-about-quality/project-planning-tools/overview/pdca-cycle.html
- Loon, Van, J. PDCA: Plan Do Check Act: http://knol.google.com/k/pdca-plan-do-check-act#
- Mindtools.com. Plan-Do-Check-Act (PDCA): http://www.mindtools.com/CXCtour/PDCA.php
Image Credit: Wikimedia Commons/Karn G. Bulsuk