Relationship Between Daily Kaizen and SPC


How Statistical Process Control Begat Daily Kaizen Activities

To many people, the relationship between Daily Kaizen and Statistical Process Control (SPC) might seem as remote as the relationship between a kangaroo and the past iconic American TV series “Friends.”  And yet, a kangaroo and “Friends” have a commonality in that each contains a “Joey.” Daily Kaizen and SPC also share a special commonality—the principles that they share.

Before discussing the relationship between a relatively new cultural habit (Daily Kaizen) and a relatively older practice that seems to have lost its popularity, sexiness, and appeal (SPC), it’s important to understand a bit of history and how the two are related.

In 1950, Dr. Edwards Deming began his semi-annual pilgrimages to Japan where he would speak to executive management of many of the largest Japanese companies.  They were a captive and eager-to-learn audience trying to bounce back from a devastating war. Deming spoke of many things, but one topic he addressed quite frequently was the importance of using statistical techniques to reduce waste to become more competitive.  He reminded the Japanese that they didn’t have much in terms of natural resources (i.e. iron ore, lumber, oil, gas, minerals), but that any savings they recognized in not wasting natural resources through the use of statistical techniques, was similar to discovering a great abundance of that same resource, right in their own homeland.

For that reason, Deming advocated the use of control charts for operators to monitor processes visually, and react quickly when out-of-control situations occurred to immediately stop further production, swarm to the problem to fix it, and then, as soon as possible, determine the root cause of the special cause variation to prevent it from ever happening again.   And so a quality revolution was born with Deming (and his cohorts Juran, Feigenbaum, and Crosby) along with SPC and Statistical Quality Control (SQC) and everyone jumped on board.  When Japan began to dominate and absorb markets, other countries began to learn about Deming’s principles.  Deming and his cohorts became not only the international gods of quality but they were also the international gods of good business.  Deming would, in fact, refuse to work with certain companies if he couldn’t speak and work directly with the CEO.  There is no business consultant today able to command that much respect.

In fact, former Chairman and President of Toyota, Shoichiro Toyoda, once said after a crisis,

 "Now more than ever, we need to remember Deming's teachings:  simply put quality first and follow through with the honest practice of developing quality products and quality people."

SPC was the “in thing”, along with other statistical tools like Design of Experiments (DOE). Many consultants made their living for many years teaching and consulting about SPC and/or DOE.   Over the years, SPC and DOE, along with other statistical techniques, were eventually gobbled up into Six Sigma.  SPC, its virtues, its values, its practices, and its popularity, slowly died because of a lack of understanding the principles behind it.  SPC was thought of as a tool and the extremely important principles behind it were overlooked or never known.

However, within Toyota and a few other companies, SPC’s principles were understood and manifested in the practices in what is now called Daily Kaizen.

So what are the common principles between true SPC and true Daily Kaizen?  True is emphasized because in many applications of Daily Kaizen, the same pitfalls that brought SPC to its knees are happening all over again.  Here are some of the most important shared principles that should be adhered to for both true SPC and true Daily Kaizen:

1.    Visual Management:  SPC is all about a visual expression of how the process is running right now.  True Daily Kaizen (via work cell Visual Management Boards and Daily Accountability Meetings/huddles) should also represent a view of how the process is running right now, daily, not weekly or monthly, but at a slightly higher level than SPC.

2.    Team Leader/Supervisor Support: In both true SPC and Daily Kaizen, the process is continuously monitored by operators, team leaders, and supervisors so that the team leader and/or supervisor can react in real time by seeing the problem as it is occurring in accordance with their Leader Standard Work and help to correct the problem.

3.    Process Focus:  SPC stands for Statistical Process Control – not product control.  Many “SPC” applications in the past and today are applications of measuring product specifications, not process specifications.  This also happens with many companies’ attempts at Daily Kaizen.  This was never the intent of SPC or Daily Kaizen.  The intent and the principles of both lie in the idea of monitoring and measuring the leading process indicators, not the lagging indicators.  In both SPC and Daily Kaizen, we should be monitoring and measuring what the team actually has control over.

4.    Real Time Data Capture:  In many applications of SPC, data is either input into an SPC program much after the actual occurrence of the event (“much” defined as many minutes, hours, or days).  The same problem comes in many Daily Kaizen attempts in that data is entered and reviewed long after the process has been completed.  The principle behind this is that a team or individual monitors real-time data as it’s happening in order to see the problem, and truly work on and fix the problem, as it occurs.

5.    Clear expectations: True SPC offers clear expectations. Out-of-control limits are clearly identified and it’s understood that if there is an out-of-control point or condition (trends and runs with clear definitions), the process is shut down.  This isn’t always followed within many SPC applications so the effectiveness of SPC is never realized.  The same can be said for many Daily Kaizen implementations.  True Daily Kaizen should offer clear production and quality expectations on Communication Cell Boards, perhaps hour by hour. If there are any deviations from these expectations, there should be immediate action.

6.    Visual Control: In true SPC and Daily Kaizen there should always be clear and visual indicators of a process that is in control/expectation and a process that is out of control/expectation.  Use of “red” is the most common indicator for processes that are not in control in an SPC application or Daily Kaizen.

7.    Root Cause Analysis: In true SPC, when an out- of-control condition exists due to a special cause, root cause analysis should be performed to determine and eliminate the root cause. In reality, this seldom happens.  In true Daily Kaizen, root cause analysis should also be performed when a process doesn’t meet expectations.  This should be demonstrated on a 5 Why’s form, a 3C (Concern, Cause, Countermeasure) form, or a CAPA (Corrective Action Preventive Action) form. In realty, for both SPC and Daily Kaizen, root cause analysis is infrequently performed effectively, which only offers us all more opportunities to improve.

8.    Respect and Operator Empowerment:  In true SPC, the intent was to grant the operator control of monitoring the process and taking the initial actions to ensure that no more defects were made.  This is also the intent of true Daily Kaizen. This often isn’t realized because respect and empowerment rarely materialize at the operator level, except at a superficial level.

The people that first learned from Dr. Deming were willing and open to embrace his principles and understood that they can be applied in many other forms … like Daily Kaizen.  Other companies that used SPC and Daily Kaizen but applied them incorrectly, looked at them as tools that could be taught and applied without management involvement, cultural change, or organizational change They failed to achieve the long term benefits of using these tools.  When this happens, when a true commitment to the principles and ideals of true SPC and Daily Kaizen is not made, failure will result.

Credit to: KaizenTM Institute