A third of a manufacturer’s non-conformances were repeats of problems already "closed". Training 40 supervisors and engineers in 8D, A3 and 5 Whys, with coaching on live problems and evidence-based reviews, cut repeat NCRs by 64% and more than doubled first-time 8D acceptance.
Key numbers
A diversified manufacturer discovered something uncomfortable when it analysed its quality records: about a third of all non-conformances were repeats of problems that had already been "closed". The corrective actions had been completed, the reports filed and the boxes ticked. The problems came back anyway. Customers had noticed, and many of the company's 8D reports were being rejected at first submission.
The situation
Repeat non-conformances were running at around 47 a quarter. Only 38% of 8D reports were accepted by customers first time. The common thread in rejected reports was weak root cause analysis: causes stated as "operator error" or "not following procedure", with corrective actions limited to retraining and reminders.
What changed
- Forty supervisors and engineers were trained in structured problem solving: 8D, A3 and 5 Whys, combined with data tools and Is/Is Not analysis, building on the methods in building a problem-solving culture with 8D and root cause analysis beyond the 5 Whys.
- Each participant was coached through a live problem from their own area, so the training produced real solutions as well as skills.
- The quality manager changed how 8Ds were reviewed: root causes had to be supported by evidence, both occurrence and escape causes had to be addressed, and "retraining" was not accepted as a corrective action on its own.
Results
Repeat non-conformances fell from around 47 a quarter to 17, a 64% reduction within a year. Customer acceptance of 8D reports at first submission rose from 38% to 86%. Forty people now had practical problem-solving skills, used daily across the business.
Why it worked
Training alone would probably not have been enough. Coaching on live problems made the methods practical, and the change in review standards made evidence-based root causes the expectation rather than the exception. Once people knew their root causes would be challenged, they began looking for real ones.
Lessons for your operation
- Count repeat non-conformances. They show whether problems are really being solved.
- Train problem-solving on live problems, with coaching.
- Review root causes for evidence, not completion.
- Do not accept retraining alone as a corrective action.
- Address both why the problem occurred and why it was not detected.
