Defect Elimination vs. Root Cause Analysis: What's the difference?
Don’t wait for a major failure. Learn how to drive continuous improvement through more proactive defect elimination and root cause analysis.
For some organizations, the lines have become blurred between defect elimination and root cause analysis. In addition, many forget that defect elimination should be an ongoing effort and not only applicable to major failures. For these reasons, it’s important to revisit the definitions of defect elimination and root cause analysis (RCA) and examine how they can be better applied to drive continuous improvement.
What is “defect elimination” and a “defect elimination program” and where does root cause analysis fit in?
“Defect Elimination” analyzes the defect, the problem, and then implements corrective actions to eliminate that defect. A defect is anything that decreases production, lessens value, impacts the environment, incurs unnecessary cost, makes things unsafe or creates risk of other issues, large or small.
Root Cause Analysis is one of several problem-solving methodologies designed to break down a defect or problem and uses cause-and-effect relationships. An example of an RCA methodology is the Cordant™ Root Cause Analysis method. Using a cause-and-effect approach enables you to identify all the causes of a problem which then provides opportunity to change, control, or eliminate causes and prevent recurrence of the problem.
A Defect Elimination program is a structured process companies adopt to become more consistent and reliable in eliminating defects and in preventing recurrence of problems across the whole business. It encompasses root cause analysis as a technique to uncover the cause and effects, as well as reporting and governance to ensure solutions are implemented and effective.
Defect elimination and root cause analysis are not just for major failures.
Defect elimination should be part of a broader continuous improvement program (see below figure 1) and be applied consistently across the operations of a company on opportunities that present themselves as significant and worthy of the effort. The first challenge always lies in identifying these opportunities.
The worth or significance of a problem is determined by understanding how impactful it is, considering the current actual impact and the potential impact. A common approach is to define the significance of a problem by using a risk matrix based on consequence and likelihood of occurrence as the parameters. The risk ranking of a problem provides clear direction about when to investigate an issue and should be the trigger for root cause analysis to occur.
Fig 1. Risk Matrix
The reality is that not all defect elimination programs have formal triggers for root cause analysis. In addition, many organizations choose to conduct root cause analysis only on major failures which are highly visible because they have caused significant downtime and production losses, or safety and environmental issues.
Figure 2. Defect Elimination Program Process
Defect Elimination, however, should be a continuous effort and not one that is limited to major failures. What some may consider to be a minor or less significant issue can still have a negative impact in terms of safety or productivity. Cumulatively, these less significant problems may also have the same impact as a single major event. So why wait for a significant event when there’s an opportunity to drive improvement through small positive changes?
Effectiveness of defect elimination relies on the quality of analysis and the quality of the solutions that are implemented
The effectiveness of any defect elimination process relies not only on the quality of the initial root cause analysis but also the quality of the selected corrective actions to be implemented.
If the analysis of the problem is of poor quality, the problem may not be fully understood, and the effectiveness of any corrective actions may be questionable. If the analysis is sound but poor choices are made as to which corrective actions to implement, then the result may not be satisfactory. In both situations, the problem is likely to recur.
So how can organizations ensure effective root cause analysis and appropriate choice of solutions?
An organization may choose to have a single Root Cause Analysis (RCA) methodology or to have a choice from several different RCA methodologies to accommodate the various complexities, significance, and nature of problems. When deemed appropriate, an RCA methodology can be chosen from the approved company list and then used to analyze the incident, accident, or defect that has occurred.
However, there is a significant benefit when a company choses to have a standard RCA methodology. Standardizing on a particular methodology—and ensuring everyone is familiar with the process and language used, enables everyone to use the same repeatable approach to analyze defects and drives the quality of the analysis to a consistently better standard. For example, everyone will be able to understand the analysis and where the solutions came from because it is the go-to process. They will also be able to comment on the quality of the analysis and indicate whether it was done well or if it needs to be revisited.
All organizations have problems. It is how effective they are in learning from these problems and preventing recurrence that drives continuous improvement.
If we choose to do the same things for the same problems, then are we really learning? Are we standing still in the sense that we aren’t doing anything different?
In this current economic climate, if we aren’t trying to do things more effectively and efficiently, doing more with less, then we are essentially standing still and missing an opportunity to improve.
Effective root cause analysis is a fundamental part of any defect elimination program and therefore a critical element in driving continuous improvement. As with all other aspects of a defect elimination program, sound planning is the key to success.
A critical element is the need to drive efforts at root cause analysis towards excellence. If the analysis is average, then the outcomes will be average too. It is the maturity and application excellence in our RCA efforts that provides the biggest bang for buck. Training people in RCA is one part of the process, but what about mentoring, RCA reviews, and the provision of feedback to facilitators? How else do we improve? This too should be subject to the continuous improvement philosophy.
We also need to consider the impact of choice when making decisions about corrective actions (i.e. the choice about which solutions to implement). Consider the hierarchy of control, a ranking system that tells us which solutions are considered best. “Soft” controls include administrative controls and PPE and are at the bottom part of the hierarchy because there is no guarantee that they will work. Still, we see more of these controls being implemented and that equates to recurrence of issues being more likely.
Of course, managers make conscious decisions about whether they reduce or mitigate the consequence of an event with a ‘soft’ control or prevent re-occurrence with a hard control. These decisions are usually based on the organization’s risk appetite, but they impact the solution’s effectiveness.
The upshot of all of this is that organizations need to have sound structures about how they go about Defect Elimination in support of initiatives that drive continuous improvement and Root Cause Analysis is a critical element within these initiatives.