‘Five Why’s’ is a commonly used tool, widely seen as one that when used well gives you answers to challenging operational problems.
Mostly it will, but what happens when the answer lies hidden outside the consideration of the effort to identify the cause-and-effect chains that lead to the problematic outcomes.
To solve any challenging problem, there are 4 stages that are used:
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- Collection of data
- Analysis, segmentation, and classification of the data
- Generation of a theory that might explain the condition and
- Experiments to identify the cause of the outcomes rather than just the observations of it.
What happens when the third stage fails to produce a theory that explains under experimentation the outcome?
Go back to the basics, by looking at the data more widely, as clearly something is missing. Often it pays to reverse the process and ask yourself ‘what could have caused this outcome’ starting at the problematic result.
Years ago, Dairy Farmers limited had a monopoly in retail UHT processed long-life custard. It was a modest sized niche market that was quite profitable. There had been several attempts by competitors to grab a piece of the action, all of which had failed. Suddenly we started having problems at seemingly random times. When opened the custard was the consistency of water. The costs of lost production were substantial, but the far greater costs were those of the product recall from retail shelves, and loss of consumer confidence.
The condition was caused by either the presence of an enzyme called amylase, or a failure of the CIP system. Amylase is a naturally occurring enzyme in starch, which had been eliminated by processing from the complex hydrocolloid (starch) ingredient we used in the custard. We had accepted the assurances of the supplier that the ingredient supplied was amylase free, as per our specifications. We assumed therefore that the problem lay with the processing plant. The plant was torn apart several times, cleaned meticulously, and on one occasion, underwent some expensive engineering changes.
All efforts failed to fix the problem.
A valuable question to ask in this circumstance is: ‘What would have to be true to…..’ In this case, the answer would have been: ‘there is no presence of amylase in the hydrocolloid ingredient’. This may have, much earlier than it did, spark the further question: ‘Is a test with a sensitivity level of 1 part per million a reliable indication that there is no amylase?
When we finally asked this question of ourselves, the answer was clearly ‘No’. We set about refining the test our suppliers used to a sensitivity of 1 part per 10 million. This more sensitive test showed up in a random manner, the presence of amylase in the supplied ingredient.
5-Why is a great tool. However, like any tool, it must be used by an expert in order to deliver an optimum result.
Header is courtesy of a free AI image generator, depicting some tortured engineers doing a root cause analysis..
