Always one root cause?

[Pau Calvo]

My company works for several T1 automotive suppliers and each one uses diferent aproches to define how many and which types of RC exist or must be identified.
I usually work with 8D methodology, that in most variations identifies 3 types of RC, occurrence root cause, detection root cause and systematic root cause.
In may experience normally a failure is not only determined by one sole cause, atleast the production process, the detection process and the system have to fail.
As example: why your inspection facility have this lightning conditions? When the process was designed was taken in account? If not you may have a issue with your process design system and this problem can occur trough several parts or projects...

 

[AMIT BALLAL]

Were these defects damage that the inspector created or were they ‘escapes’ that the inspector failed to ‘catch’?

So you have data that proves that the inspector who was ‘tired’ because they worked double shifts was the primary source of the ‘defects’? What was their defect rate compared to other inspectors? Did this inspector’s defect rate go down when they only worked 1 shift?

How did you determine that poor lighting was a secondary cause of defects?


Forget the talk about fishbone diagrams and why-why. These are only guessing and questions that try to lead you in the right direction. It is the data that answers the questions and proves the conclusions or claims of causality. Can you answer the above questions?

What I understood based on all the information shared by qualprod is it is for non-detection of defect (not occurrence).
qualprod, please correct me if I'm wrong.

 

[Randy]

"Frequent bad inspection of product, which cause rejects." Well then beat the inspectors, strike fear into their hearts. Give 'em a time out.

Seriously could it be something as simple as they really aren't sure what is good and what isn't? or
They're hesitant to fail something because of potential upstream and downstream problems within the organization itself that could occur. or
Your inspectors just don't care one way or the other?

Sometimes cause analysis isn't scientific, mumbo-jumbo, requiring charts and graphs and super-duper analysis, it's just people being people.

 

[Bev D]

to be clear I've never used mumbo-jumbo or 'super-duper' analysis in terms of people but I also haven't used guesses hunches or bias that people are just plain lazy and incompetent. good cause analysis still requires evidence and data at some level - not theories and not over-analysis.

 

[Randy]

A long, long time ago when my Attack Helicopter Troop was putting on a live fire demonstration for our Governor (some guy named Clinton if I remember correctly) and other dignitaries, one of our #1 gun pilots, clear of mind, so far beyond basic competence it was off the scale and probably 10,000 plus hours of stick time touched the wrong button and instead of firing 18 2.75 inch rockets, each containing 17 pounds of very high explosive were jettisoned and rolled across the ground about 75 feet below us going every way but the one intended, relieved of out load we went up like a runaway elevator nearly out of control....The outcome of this adventure resulted in an investigation by the Army Aviation Safety Office and you know what the outcome was....Oops! George said that he had just touched the wrong button, I saw him touch the wrong button, and our unit commander in the other seat told George at the time "You hit the wrong button" All the cause analysis, all of the investigation with charts, graphs and everything else resulted in what we knew from the start ...Oops you touched the wrong button. That's what I was getting at, the defects can be nothing more than....Oops and not a slam at people or anything else.

 

[qualprod]

to be clear I've never used mumbo-jumbo or 'super-duper' analysis in terms of people but I also haven't used guesses hunches or bias that people are just plain lazy and incompetent. good cause analysis still requires evidence and data at some level - not theories and not over-analysis.

"Frequent bad inspection of product, which cause rejects." Well then beat the inspectors, strike fear into their hearts. Give 'em a time out.

Seriously could it be something as simple as they really aren't sure what is good and what isn't? or
They're hesitant to fail something because of potential upstream and downstream problems within the organization itself that could occur. or
Your inspectors just don't care one way or the other?

Sometimes cause analysis isn't scientific, mumbo-jumbo, requiring charts and graphs and super-duper analysis, it's just people being people.

Amit
Yes, were non detected problems

Randy
They are capable ( have the competence, knowledge, know the criteria to accept o reject product) the
problems happend because inspector was tired (working two shifts for three continuous weeks) and when outside is cloudy,
the light into the inspection room is not adequate (light affects directly at inspections).
Have to detect deltas of tones in colors in labels.
Hope my explanation is clear.

 

[Jim Wynne]

Amit
Yes, were non detected problems

Randy
They are capable ( have the competence, knowledge, know the criteria to accept o reject product) the
problems happend because inspector was tired (working two shifts for three continuous weeks) and when outside is cloudy,
the light into the inspection room is not adequate (light affects directly at inspections).
Have to detect deltas of tones in colors in labels.
Hope my explanation is clear.

When everything is messed up, everything needs to be fixed.

 

[Mike S.]

Amit
Yes, were non detected problems

Randy
They are capable ( have the competence, knowledge, know the criteria to accept o reject product) the
problems happend because inspector was tired (working two shifts for three continuous weeks) and when outside is cloudy,
the light into the inspection room is not adequate (light affects directly at inspections).
Have to detect deltas of tones in colors in labels.
Hope my explanation is clear.

If nonconforming material gets through Inspection because of the reasons listed above, it is not a failure on the part of the Inspector(s) it is the failure of Management for grossly overworking their Inspectors and failing to provide adequate resources.

Before blaming people you need to very honestly and thoroughly consider whether or not they had adequate support/facilities/tools, standards, procedures, training, and leadership.

And sometimes, even if you have all of the above, you have the very rare situation that Randy described -- an unexplainable "oops" that can't be anticipated. When the consequences of such an "oops" could be catastrophic you try to build in redundant failsafes and hope and pray they are enough.

Maybe Bill just attracted these kinda events. Also down south in Clinton country, when he was just a Governor, a technician dropped a wrench in a Titan II missile silo and caused a chain of events that caued a huge conventional explosion that killed a few people, but could have resulted in the annihilation of every living thing within a radius of several miles. Risk is all about considering probability and consequences.

 

[Marc]

a technician dropped a wrench in a Titan II missile silo

1980 Damascus Titan missile explosion - Wikipedia

Also - Watch Command and Control, Full Film | Season 29 Episode 1 | American Experience

 

[Randy]

1980 Damascus Titan missile explosion - Wikipedia

Also - Watch Command and Control, Full Film | Season 29 Episode 1 | American Experience

Yep, I was standing about 1/4 mile away from it when the thing blew and I knew many of the people involved.