A young Production Manager finally gives the green light to implement his latest Kaizen process improvement after several weeks of data collection, testing, and planning. John has been working closely with his cross- functional team to find the optimal filler settings to improve weight control and reduce product give-away. This yield improvement project should save $200,000 annually. It will make the difference between either exceeding or falling short of his critical goals for the year. John knows better than to sit at his desk patting himself on the back at this point though, he has much more work to be done. John plans to follow-up with the operators to make sure everything is going as planned but there are other pressing issues and follow-up will have to wait for another day. The next morning brings more urgent issues and the next thing he knows it has been a month and the expected results just are not there.
Sound familiar? What could have gone wrong? Even if John and his team were working through the DMAIC Process (Define, Measure, Analyze,Improve, Control), there are potential pitfalls along the journey:
One common pitfall is jumping to a false conclusion. Teams don’t always dig deep enough to get to the true root cause. If John’s team fully implements the countermeasures but have repeat issues, they probably did not get to the true root cause. For example, the filler settings could have only been part of the problem in John’s case. Deeper analysis would have revealed that overdue maintenance caused inconsistent fill weights. In short, they’re solving the wrong problem. The 5-Why analysis is a great tool to find the root cause or as is often the case, multiple rootcauses of an issue. Briefly, 5 – why analysis is like the 3-year-old that constantly ask why? Why do we run all the predicted orders for gourmet jalapeño cheese filled pretzels in one day? Because that is the way we always do it. Then why have we continued? Because no one said we should change. Why do we have overproduction of jalapeño cheese filled pretzels when we run that product only for a day? Because we run it on Mondays and we are still waiting for orders. The process continues until the root cause or some combination of causes is judged as the root cause. Practicing lean thinkers usually ask 4 or 5 why questions per issue – sometimes more and occasionally less. A team that is capable of discovering the root cause is often perfectly capable of finding a satisfactory countermeasure for each root cause.
Have you seen teams miss the true root cause? Do you have examples you can share where teams hit the mark and have sustained improvements?
Teams must get to the true root cause to achieve sustainable improvements. Use the 5 Why method.
Dr. Glen Miller & Christian Paulsen
The preceding is the first of a three part series of posts on Sustaining the Gain when implementing Lean improvements. It is co-authored by Dr. Glen Miller and Christian Paulsen. You can go to part 2 of Sustain the Gain here.
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