Corrective Actions - Getting to the True Root Cause

[Willyboy]

Hello again.

Below is a CA report that was filled out by our company's shop manager with the help of our QA manager. I know that I can get wordy at times in my descriptions and questions, but if someone(s) could give me their thoughts, I'd be very grateful.

Before we get started, I need to tell you that my opinion is that the “true root cause” has not been found and/or discussed. Here we go.

The explanation of the issue is: “Employees assembled bag incorrectly.”

The root cause (singular cause, not plural) using 5 whys is given as:

Employee assembled package incorrectly.
Did not refer to sample.
They forgot there was a sample.
Were not shown where the sample was.
Employees were not reminded to refer to sample.

Immediate Action is given as:

Incorrect product was reassembled.
Sample given to each employee to follow.

Corrective/Preventive Action is given as:

Retrain employees to follow procedures.

Summary/Final Review is given as:

Follow up when job returns to shop.

As I stated at the beginning, I do not believe that the “true root cause” has been found or discussed. Why?
Because there is no explanation of “how” the bags were assembled incorrectly.

Were they not sealed but should have been? Were they sealed but should not have been? If they were supposed to be sealed, were they sealed too tight? Too loose? At an angle? Did the bags have the wrong parts in them? Too many parts? Not enough parts? Was the wrong bag used?

I believe that the root cause items given:

“Employee assemble package incorrectly.
Did not refer to sample.
They forgot there was a sample.
Were not shown were the sample was.
Employees were not reminded to refer to sample.”

are possible starting places, but until we know “how” they were assembled incorrectly, I do not feel that we can get into the “why”.

If the management can sit down with the employees and show them with a sample the correct way to assemble the bags/packages, will this suffice? It might fix this particular issue, but I do not believe that is very preventive of similar incidents that may occur due to sealing the bags, not sealing, wrong parts, etc.

As always, thanks.

Bill

 

[AndyN]

Re: Corrective Actions getting to the root cause?

The reason is in the first line of your post.........

Any CA filled out by (two) managers only is cause for concern. We all know (well, they apparently don't) that improvement comes from involving the people who operate the process.

I'm guessing here, but I believe you've got a task of educating your team on CA tools and techniques, not just filling out 5 Whys.....

 

[Cari Spears]

Re: Corrective Actions getting to the root cause?

Were they not sealed but should have been? Were they sealed but should not have been? If they were supposed to be sealed, were they sealed too tight? Too loose? At an angle? Did the bags have the wrong parts in them? Too many parts? Not enough parts? Was the wrong bag used?

I believe that the root cause items given:

“Employee assemble package incorrectly.
Did not refer to sample.
They forgot there was a sample.
Were not shown were the sample was.
Employees were not reminded to refer to sample.”

are possible starting places, but until we know “how” they were assembled incorrectly, I do not feel that we can get into the “why”.

If the management can sit down with the employees and show them with a sample the correct way to assemble the bags/packages, will this suffice? It might fix this particular issue, but I do not believe that is very preventive of similar incidents that may occur due to sealing the bags, not sealing, wrong parts, etc.

"A problem well defined is a problem half-solved." –John Dewey

I agree with you - "Employee assembled package incorrectly" is not a well defined problem.

Here are our Corrective Action Form and our Nonconforming Product Tag; you'll notice both require what the specification/requirement is and what the actual condition is.

I would be looking for some way to mistake proof the process. People make mistakes because the process allows them to.

Do you know what was wrong with the packaging? Perhaps you can present them with how you would like to have seen it written up and resolved.

 

[howste]

Re: Corrective Actions getting to the root cause?

My first thought was that the problem statement shouldn't be “employees assembled bag incorrectly” it should be “misassembled bag.” If the problem statement itself starts by blaming the employees, the corrective action process is doomed to identify a cause that's not systemic.

Beyond that, I need to know more details of what was not assembled correctly, what the assembly conditions were, any mistake proofing in place, etc. in order to go any further with cause analysis.

 

[Cari Spears]

Re: Corrective Actions getting to the root cause?

If the problem statement itself starts by blaming the employees, the corrective action process is doomed to identify a cause that's not systemic.

Exactly!

 

[Willyboy]

Re: Corrective Actions getting to the root cause?

Everyone,

I failed to explain clearly. The issue was discussed with the employees, but it was the floor manager and QA manager that oversaw the discussion and filled out the paper work.

Cari, the forms you have are fairly close to what we came up with.

Andy, you are correct. We need to learn how to use the tools and techniques.

As to more detail, I am currently looking at the CAR and it does not give a part number, working conditions or any detail that I feel should be there.

One of my other concerns was for our Management Review meeting tomorrow. How is upper management supposed to know if problems are being addressed if the floor manager and QA person are not being specific in the problem descriptions?

How are the floor manager and QA person going to remember the specific issue a month or year from now?

How are the employees going to come up with possible solutions if the true cause is not known?

In other words, if the problem is not well defined, then it is not half solved.

Howste, the reply about not beginning by blaming the employees is very insightful.

Wow. You guys and gals are making me think!! As I mentioned in previous posts, I am new to the IA job and am trying to feel my way through it.

Thanks.

Bill

 

[Jim Wynne]

Re: Corrective Actions getting to the root cause?

My first thought was that the problem statement shouldn't be “employees assembled bag incorrectly” it should be “misassembled bag.” If the problem statement itself starts by blaming the employees, the corrective action process is doomed to identify a cause that's not systemic.

I think there's a common misunderstanding of how root cause analysis should proceed. In my view, there's nothing inherently wrong with starting from an assumption that employee error was the cause. The problem is that we need to have a better understanding of the basic scientific method, keeping in mind that science is, in general, a search for the causes of things.

You need to start with an hypothesis, which is a provisional, tentative explanation of an observed phenomenon, in this case the mis-assembled bag. Once the problem (the observed phenomenon) has been described, most people intuitively think that the next step is to find evidence that the hypothesis is correct. What should happen, however, is a search for evidence that the hypothesis is wrong. If you only search for evidence that your initial hypothesis is correct, it's far too easy to find misleading evidence.

BTW, the reason I don't like the "5 whys" is that it's too often misapplied; it's a good way to make sure you have a good description of the problem, but not so helpful in finding causes. For example, it's been pointed out that the description of the problem in the present case doesn't provide enough information, and it could have been made better by asking "Why?" a few times. For finding the root cause, however, we should be asking (in view of the working hypothesis) "Why not?"

 

[adamsjm]

Re: Corrective Actions getting to the root cause?

My first thought was that the problem statement shouldn't be “employees assembled bag incorrectly” it should be “misassembled bag.” If the problem statement itself starts by blaming the employees, the corrective action process is doomed to identify a cause that's not systemic.

Absolutely TRUE! Companies who perform good corrective actions limit the employee’s participation (and, therefore, the use of “re-train”) in the root cause to 3%. So, what caused the other 97%? We must look at the system and its management.

Per your initial comments from the CA, the first why (of the 5-Why process) could be:
“How or why did the job start without the reference assembly sample NOT at the assembly station?”

Additional questions would be:

Associates “forgot” or “were not shown” where the samples are kept? Why is the location not listed in the equipment section of the Work Instruction?

Associates “did not refer to sample” or “were not reminded to refer to sample”. Why is this not identified on the Work Instruction? Did the operator sign-off that they had read and understand the Work Instruction prior to starting the operation? Did the supervisor check with the operator if any clarification was necessary?

If the “Immediate Action” was “Sample given to each employee to follow”, were they also given the procedure that they are supposed to follow? (i.e.: Retrain employees to follow procedures) Or is the procedure to follow what management thinks you ought to do that day – “Do what I say, not what wrote, if I did write it down.”

Why is the “Summary/Final Review is given as: Follow up when job returns to shop” and not audit all other assembly operations which require control samples?

Good Luck in changing your company’s culture.

Joe

 

[Jim Wynne]

Re: Corrective Actions getting to the root cause?

Absolutely TRUE! Companies who perform good corrective actions limit the employee’s participation (and, therefore, the use of “re-train”) in the root cause to 3%. So, what caused the other 97%? We must look at the system and its management.

I don't think it's helpful to apply an arbitrary, unsupported standard (3%) to these things. Each case should be evaluated on its own merits.

 

[adamsjm]

Re: Corrective Actions getting to the root cause?

I don't think it's helpful to apply an arbitrary, unsupported standard (3%) to these things. Each case should be evaluated on its own merits.

It is not a “standard”, it is a maximum allowable value. The system owners want to take the easy way out and blame the operator when, in fact, the system failed the operator. The system did not provide for the proper tooling (do you have a left-handed operator operating a right-handed machine?), proper flow (if non-conforming material does not flow 180 degrees away from the conforming material flow path, it WILL find its way back into standard flow), adequate space, good lighting, etc. Basically, the operator cannot cause a failure. They can only point out weaknesses of the system. The 3% opportunity is to allow the system owners and management to lay some blame on the operator and, thereby, feel better.

If the operator truly caused a failure, they had to do so purposefully. Follow Deming’s writings and fire them if necessary.

Joe

P.S.: By following the above concept to identify product and tooling changes, a team reduced scrap rates of a product line that used 288,000 parts and assemblies per day from 40% to 0.05% in 3 months and achieve almost zero process failures (0.03 DPMO) within 12 months and making 55% EBIT.