User Errors and Product Nonconformances

#1
Wondering: Is a product failing to meet a requirement still considered non-conforming if its failure to meet the requirement was due to actions of the user?

For example, consider the following sequence of events:
  1. Product requirement is "sensor responds correctly to user movement".
  2. Complaint is received that "sensor is all out of wack", and they want to return the device. Device is returned.
  3. Device received and checked, and indeed sensor appears to not be working correctly. Product NCR filed.
  4. As part of NC investigation it is determined that there is actually nothing wrong with the sensor. The customer (undisclosed) had simply recalibrated the device incorrectly.
In this example, is this actually a product non-conformance? When reported, the device was clearly failing to meet the requirement. But on further inspection it was actually behaving exactly as you'd expect given the user's misuse (error?) of the device.

Curious to know what you think...
MM.
 

John Broomfield

Fully retired...
Trusted
#3
Wondering: Is a product failing to meet a requirement still considered non-conforming if its failure to meet the requirement was due to actions of the user?

For example, consider the following sequence of events:
  1. Product requirement is "sensor responds correctly to user movement".
  2. Complaint is received that "sensor is all out of wack", and they want to return the device. Device is returned.
  3. Device received and checked, and indeed sensor appears to not be working correctly. Product NCR filed.
  4. As part of NC investigation it is determined that there is actually nothing wrong with the sensor. The customer (undisclosed) had simply recalibrated the device incorrectly.
In this example, is this actually a product non-conformance? When reported, the device was clearly failing to meet the requirement. But on further inspection it was actually behaving exactly as you'd expect given the user's misuse (error?) of the device.

Curious to know what you think...
MM.
Mark,

It seems to me that you are not done yet.

Two possible causes flowing from your investigation of this nonconformity:

1. The calibration instructions failed to meet the requirements of the customer.

2. The device needs mistake-proofing so the customer cannot use it incorrectly.

Or, you may just have a service or business opportunity to train customers in their proper calibration and use of the device.

John
 
#4
The calibration process is a relatively obscure feature, intended only for over-the-phone troubleshooting. As I say, not disclosed in this case.

...but really it's just an example. I'm more interested in the principle, and categorization (documentation) practices in such cases. If a product non-conformance is defined as simply not meeting a requirement or specification, is product not meeting a requirement due to the actions of a user still considered "non-conforming"?

You use the word "defective". Would you say this is synonymous with "non-conforming"?

Perhaps the requirements specifications need to just be more specific, to specifically exclude cases where user action is the cause.
 

Bev D

Heretical Statistician
Staff member
Super Moderator
#5
Interesting question.

To my way of thinking, “defective” is not synonymous with “non-conforming”. If the requirements - or specifications - are wrong, a product may be defective and stilll conforming. It may also be non-conforming and still quite able to function as intended. From a legal standpoint, the two terms are also quite different. For example, a latent defect may not be apparent until some stress has uncovered it. So a part can be defective yet meet requirements for some time.

As to your original question, this is more of a gray area. A product that is altered by the Customer and then returned may in fact be non-conforming and require control to prevent shipping it back out in a non-conforming state regardless of the source of non-conformance. Once you accept it back it is now your responsibility. Further investigation would be required to determine how the Customer would have altered the product. While we can’t necessarily control malicious alterations, we can control misguided or “incompetent” alterations through error-proofing. We can also determine what caused the Customer to believe that they had to alter the product in some way - adn then take action against that. Typically these two actions are based on how frequently this occurs. If there are only a very few occurrences it may not be worth a lot of effort. If it is fairly frequent then it may be teh right thing to do to maintain Custoerm loyalty.
 

Mike S.

An Early 'Cover'
#6
In this example, is this actually a product non-conformance? When reported, the device was clearly failing to meet the requirement. But on further inspection it was actually behaving exactly as you'd expect given the user's misuse (error?) of the device.

Curious to know what you think...
MM.
The key here to me is if the user indeed "misused" the device, and knew, or should have known, not to do that. For example, if you have an easily accessed screw that says "calibration" and no prominent instruction not to touch it, or it is not covered by a tamper-resistant cover, etc. then you might expect a user to fiddle with it, and I'd say you are inviting trouble.

If a user destroyed a tamper-resistant cover to fiddle with the screw, I'd say the user is totally at fault.
 

mlee97

Involved In Discussions
#7
If the customer's perception is that it is defective, then your product has failed to meet the customer's requirements. It might meet yours, but you're not the purchaser.

If you plan to stay in the business of producing this product, then there is a clear need to improve your product's sensor calibration or what-ever.

The quality system standards of today are geared toward making a business better and stronger by staying relevant to stakeholder requirements and addressing risks. The problem of having dissatisfied customers is definitely a risk to your company.

So in a nutshell, I would say yes the part is a non-conformance as its design or its instructions do not meet customer expectation.
 
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#8
So in a nutshell, I would say yes the part is a non-conformance as its design or its instructions do not meet customer expectation.
I'm a bit wary to tie the QMS non-conforming product process to something so subjective. Ideally, the requirements/specifications would be clearly documented so that the decision to issue an NCR is clear. If not meeting customer expectations is grounds for product NC, then pretty much every single complaint would spin out an NCR, no?

Consider: If a customer called in a complaint and said simply "I don't like the product", would you consider this a product non-conformance as it "[did] not meet customer expectation"?
 

John Broomfield

Fully retired...
Trusted
#9
I'm a bit wary to tie the QMS non-conforming product process to something so subjective. Ideally, the requirements/specifications would be clearly documented so that the decision to issue an NCR is clear. If not meeting customer expectations is grounds for product NC, then pretty much every single complaint would spin out an NCR, no?

Consider: If a customer called in a complaint and said simply "I don't like the product", would you consider this a product non-conformance as it "[did] not meet customer expectation"?
Mark,

Well, yes. Your sales process let the customer and the organization down.

But problems like this do not receive corrective action to stop recurrence until a lot of bigger problems have been solved.

No need to raise the NCR unless you have a nonconforming product to control and disposition. You could consider going straight to a CAR after your risk assessment.

Your documented risk assessment could state “do nothing” until the bigger problems have been solved for good.

John
 

Mike S.

An Early 'Cover'
#10
The customer is NOT always right. The customer is always the customer, and we should not forget that.

But many a customer has misused or abused a product and then said they didn't like the product. That is not a failure on the organization's fault -- Sales, Design, or any other function.

Say I make lawn mowers and you bought one and it worked fine all summer. The engine speed is self-governed to 2800 RPM. You went on vacation and did not mow for 3 weeks and now you have foot-tall grass and you decide to bypass the engine-speed governor with a spring from your parts collection and it runs the motor at 3800 RPM so it cuts the tall grass faster. Halfway through your mowing the engine blows up. You say you don't like my mower.

Who's at fault?
 

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