Quality & Law Enforcement: Detection vs. Prevention

During a kaizen workshop, the kaizen team identified the lack of value-added content in the final inspection process. This led to an interesting comparison of quality systems that do not practice Lean manufacturing principles, with the American criminal justice system.

The Drawbacks of Relying on Final Inspections for Quality Control in Lean Thinking

In Lean thinking, relying on a final inspection to catch defects is not ideal. By this point, the problems have already occurred, and if you are batch processing, there’s a higher likelihood that multiple defects will need to be addressed through scrapping, reworking, or other means. As a general rule of thumb, the cost of correcting a defect increases by 10 times when it is detected each step later in the process.

Defect Prevention: The Focus of Quality Control in Lean Thinking

Lean thinking says you check and guarantee 100% quality in-process. Promptly reporting feedback about poor quality is very important. You do root cause analysis and put in countermeasures, such as pokayoke devices (mistake-proofing). The focus is on defect prevention rather than catching and locking up defects.

The Non-Lean Approach of the Criminal Justice System

Our criminal justice system takes the non-Lean approach. Law enforcement typically prioritizes catching and incarcerating individuals who exhibit defective or unlawful behavior, with some exceptions like Victim Offender Reconciliation and Restorative Justice Programs. However, the focus on early detection, root cause analysis, and prevention is often lacking.

Applying Lean Principles to the Criminal Justice System

Lean practitioners know how much more expensive final inspection and correction is than early detection and mistake proofing. Perhaps the cost of our criminal justice and incarceration systems would be lower if the focus was on prevention rather than detection.

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