June 14, 2020
Let’s face it, mistakes and defects kill schedules, cause unplanned costs, and are just plain frustrating. Is it possible to never make a mistake or eliminate defects? Probably not completely, but much can be done to prevent them.
Test and Inspection
First, one must put test and inspection into the correct perspective and decide that reliance alone on detection and correction is futile. The truth is that test and inspection only detect a mistake. In other words – it’s too late, the defect has already occurred. At this point, corrective action is required. Regretfully, most approaches to corrective action deal only with the immediate problem — ie: perhaps a part was assembled wrong and the corrective action is to assemble the part correctly. Unfortunately, this is where most corrective action ends.
The first step to achieving a mistake-free environment is to learn from every mistake by asking the deeper question: “What caused this mistake in the first place?” Once the source of the problem is clearly known then a solution that prevents future occurrence is possible. There is no substitute for effective root cause analysis and a commitment to not repeat a mistake.
Assume Positive Intent
Second, start with the powerful assumption that the person performing the task wants to do a good job and they cannot just make a mistake. This forces you to think beyond the “operator error” or “humans make mistakes” notions. Consider the antecedents to providing a mistake-free environment. Ask questions like: Are there barriers to performing the task correctly? Is the work environment suitable for the task (lighting, space, organization)? Are there frequent interruptions? Is the procedure well documented? Is the person effectively trained? Do the person’s skills match up to the task? We are often quick to blame the performer when the real problem is in the antecedents.
Third, anticipate mistakes and put in place preventative measures by developing and using a process to systematically evaluate work procedures and product designs for mistake potential and severity. A popular and easy to use method is FMEA (Failure Mode and Effect Analysis). FMEA used early in the design of procedures and products has proven very effective in the identification of potential failures, their effect, probability, severity and detectability. This process causes one to consider the kinds of problems that can occur, helps prioritize them, and asks what control measures should be put into place proactively to prevent mistakes.
Minor Defects Become Big Ones
Fourth, minor defects become big ones. A good friend of mine once pointed out the logic of Rosanne Roseannadana of SNL fame who often said, “It’s always something, if it’s not one thing, it’s another.” There are problems waiting to happen everywhere and everything is subject to the natural law of entropy. As such, when things deteriorate their potential to become or create defects increases. Consider a machine building widgets that must have a precise dimension. As the machine wears out from use the ability to achieve the tolerance diminishes. Or consider the paint on your car. A minor ding in the paint over time turns to hidden rust and before long you have a major repair. Wouldn’t it be better to correct the wear out or rust out potential before the point of no return? Total Productive Maintenance (TPM) teaches us to be vigilant and look for the indicators of a future defect then act before they become a problem. An approach that corrects minor defects proactively has proven time and again to reduce the “something is going to get you” random nature of defects.
Finally, manage behaviors. If it is true that structure influences behavior, then we might ask: What structures have we put in place to achieve the mistake and defect free behaviors we desire? We must examine our reward systems to ensure we are not rewarding people for taking shortcuts. We need to think about how we hold each other accountable for doing the right thing the right way. There are many good models for behavioral management like Behavioral Safety but unless they are integrated into the culture of your business they will become just another program of the month. Teaching people correct behaviors and providing behavior prompts make a world of difference in attitudes towards defects. For example: Teaching an assembler to count out the number of screws to be assembled, driving them, then asking “do I have any loose screws?” (pun intended) is effective at preventing missing screws when compared to an assembler taking screws directly from a bulk bin. Teaching people to hold each other accountable in a systematic way is also part of the behavioral system – co-workers observing each other’s behaviors and giving safe immediate feedback can be very powerful when the expectations are clear. For example: adopt zero tolerance for improper use of safety equipment and teach people to check each other. These minor changes in behavior have enormous defect reduction potential and can also build great working relationships.
To achieve zero defects, zero accidents, and zero mistakes one must commit to an integrated system of vision, culture, expectations, procedures, personal commitments, mutual accountability, and behaviors.