A Reflection on the Application, Advantages and Limitations of Deming Cycle to Quality Problem-Solving Activities
By Dr Goh Seh Kai
7 Aug 2021
This article shares my views on the application, advantages and limitations of the Deming Cycle to quality problem-solving activities.
Deming Cycle was developed from the Shewhart Cycle, originated by the American physicist, engineer and statistician, Dr Walter A. Shewhart (1891 -1967) in 1920.
An American engineer, statistician, professor and management consultant, Dr William Edwards Deming (1900–1993), modified the Shewhart Cycle to Deming Cycle and popularized it in 1950.
In most organizations, managers might face long-term and challenging problems, such as unsatisfactory quality and productivity performance, etc., and have to address them in the long run.
Although the Deming Cycle has some limitations, I think it could be a helpful method for supporting managers’ problem-solving initiatives.
For instance, if a production process constantly encounters a high defective ratio, the production manager could continuously reduce it by leveraging quality improvement teams (QITs) with the Deming Cycle approach.
The following illustrates how managers can leverage QITs and apply the Deming Cycle concept for solving quality problems and their advantages and limitations.
Typical Quality Problem-Solving Activities for QITs
QITs usually embark on the following quality problem-solving activities to understand the main types of defects, determine their root causes, and propose solutions to reduce the overall defective ratio.
· Collect data on the various types of defects and categorize them for better understanding.
· Analyze the categories of defects to determine the few and vital types — 20% of defects for causing 80% of overall defective ratio.
· Set a target for reducing the overall defective rate.
· Focus on the vital defect with the highest defective percentage first and brainstorm possible causes caused by the worker, machine, material, facility problems, etc.
· Look into the most likely causes of the defect under investigation and identify the root causes through experimentation, observation, etc. and data collection.
· Brainstorm the possible solutions, such as machine parts modification, revised working procedures, use of superior material quality, etc., to the identified root causes.
· Select the most feasible solutions to the identified root causes and test them on a small scale (trial run).
· Confirm the most feasible solutions by collecting data to verify that their implementation can significantly reduce the overall defective ratio.
· Assess whether the problem-solving tasks have reduced the overall defective rate to meet the target.
· Recommend managers implement the confirmed solutions to all processes on a large scale.
· Take corrective actions to improve efficiency and effectiveness or revise the target set if necessary.
· Continue to tackle other defects with the highest defective percentage by repeating the problem-solving activities mentioned above.
How QITs can Apply Deming Cycle to Quality Problem-Solving Activities
QITs can adhere to the following iterative Deming Cycle approach to perform the problem-solving tasks mentioned above — continuously plan, do, check, and take corrective actions to reduce the overall defective ratio.
Plan Stage — It is the first step that QITs needs to plan how to materialize the above-mentioned problem-solving activities in the “Do”, “Check”, and “Act” stages.
With a plan, team members will know which of the above quality problem-solving activities they must perform and where and when they shall carry out these tasks.
It will also dictate how they shall implement the above activities and who needs to do them during their project activities.
It is like having a compass to guide a team’s direction during its excursion in a jungle.
As a result of proper planning, QITs can solve quality problems more efficiently and effectively.
They will understand the main types of defects, uncover their root causes and determine the solutions to reduce the overall defective rate to meet their targets.
QITs can also estimate the budget and resources required for the project during the “Plan” stage.
Do Stage — Perform the tasks stipulated in the ‘Plan” stage, such as data collection and analyses, brainstorm and identifying root causes and solutions.
QITs’ members shall follow their assigned duties to perform the above-mentioned problem-solving tasks according to the planned schedule.
Team members are responsible for applying their process knowledge and problem-solving skills and ensuring the collected data are accurate and reliable.
Furthermore, they need to propose and implement feasible solutions and ensure the project activities have progressed as planned.
Also, team members ought to exhibit teamwork spirit and constantly support one another during their problem-solving activities.
Check Stage — Regularly check what tasks have been done and what results have been achieved in the “Do” stage.
In this stage, QITs’ leaders and members must check if their work activities have progressed as planned and if the overall defective ratio has reduced after implementing solutions.
QITs’ leaders need to obtain feedback from members from time to time regarding any issues that they have encountered — such as low morale, lack of stamina, challenges, etc. — and find ways to address them.
They have to check if the team’s progress is on the right track towards its mission, objectives and goals are attained.
For example, they must assess if the identified causes are accurate and how much the trial solutions have helped reduce the overall defective ratio.
Also, they ought to measure if the actual performance has met the target set. Finally, they shall again check any working issues, and external help or supports from top management are needed.
These assessments will advise team members on what corrective actions to take in the “Action” stage.
Action Stage — Take remedial actions based on the “check” stage results — When members take corrective measures to eliminate obstacles affecting work progress and close the gap between the actual results and set goals.
Some of the issues that required rectification might be wrong root causes, inappropriate solutions, unrealistic targets, team conflicts, poor teamwork, etc.
Taking appropriate corrective actions is essential to ensuring project teams progress as planned.
For example, motivate team members by rewarding them or recognizing their effort. In addition, training and upgrading team members’ process knowledge and data analytical and problem-solving skills are paramount to team performance.
Gaining external supports, such as expert advice and additional budget from top management, is also essential to team progression.
Advantages of Deming Cycle
· Simple and Logical Approach: The method is logical and straightforward to follow — continuously and repeatedly planning what to achieve, doing what is planned, checking what has been done, and taking necessary corrective actions in an iterative cycle.
The technique always guides QITs members on which stage they are in and which step they shall act.
Without following the approach, it is more challenging to ensure the whole team will move unified, although all team members might have possessed the required process knowledge and problem-solving skills.
· Beneficial for Continuous Improvement: Due to long-term and challenging issues, QITs require a systematic and persistent way, such as the Deming Cycle, to solve them.
Without a consistent approach, it will be challenging for the teams to improve continuously as the team activities involve many members and require excellent communication, collaboration, coordination and team effort.
By following the Deming Cycle, QITs can always schedule activities, assign roles and responsibilities to team members, assess their performance and take corrective actions.
Limitations of Deming Cycle
· Inflexible to Changes: As QITs stick to their plan, they tend to be inflexible in responding to external changes in their problem-solving endeavour.
For example, suppose pressing issues emerge that require urgent actions, such as new customer specifications, new technological requirements, etc.
In that case, QITs might not easily change their plans to address them, especially when they are in the “Do” stage.
Therefore, managers will need to quickly form new problem-solving QITs to tackle the recent issues to avoid disrupting the existing team activities.
· Require Other Discipline: Solely relying on the Deming Cycle will not warrant QITs’ success in addressing quality issues.
As elaborated above, QITs shall possess process knowledge, data collection and analytical abilities, problem-solving skills, teamwork spirit, etc.
For example, QITs should be familiar with the seven quality tools: histogram, Pareto chart, cause-and-effect diagram, statistical control chart, etc.
Also, they shall understand how the processes work to identify problems and causes and propose logical solutions.
Furthermore, QITs members shall persevere and endure despite setbacks encountered and possess team spirit to support one another.
In conclusion, Deming Cycle is an appropriate method that is helpful for QITs to address any long-term and challenging problems. Furthermore, it helps QITs perform their quality problem-solving activities more systematically and persistently.
QITs’ leaders can iteratively plan what tasks members should do, check, and act accordingly to accomplish goals and the required resources and budget.
However, despite its advantages, the Deming Cycle has limitations, such as inflexibility to changes. QITs must also process knowledge, problem-solving skills, teamwork spirits, perseverance and endurance to complement it.
Thank you for reading, and your feedback is welcome and appreciated!
