Don't Say "Zero Defects" Unless You Really Mean It

[leftoverture]

You are right. In reality, the only way to get "zero" defects is some type of non-human 100 inspection system. We had a molder a few doors down, did mainly automotive stuff, and yes every mold he sold also came with the inspection gear to ensure zero defects. Like you, we do smaller volumes and have customers want "zero defects." Problem is the cost to inspect for that is more than the annual volume of parts. And the defects we usually end up with (maybe 1-2 pcs. per 10,000+) are caused by rough handling during shipping.

As for "goals," we had a similar conversation with our auditor. End result was that a "goal" has to be achievable, but a "target" can be aspirational. Se we set our delivery goal at 90% and our delivery target at 100%, etc.

Let me be perfectly clear, I do not believe in inspecting quality in...but economically speaking, it is sometimes the less expensive option versus designing or error-proofing defects out of the process. As for your molder "a few doors down" I have yet to see an automated inspection system that can deliver zero defects in the molding environment. Today's AI camera systems are coming close, but there are so many potential defects that it's close to impossible to program a camera for them all. Just when you think you've got it, a piece of coring will break that you never thought could! So in molding, automated inspection is typically programmed for the most critical defects, such as a missing insert or a short shot.

 

[leftoverture]

Where here's the deal as far as I'm concerned.........."0-ZERO" means "0-ZERO" not some equation or portion, percentage or decimal level, it means NONE-ZILCH-NADA-CERO-NULL-and so on.

So I don't care if you make 10-100-1000 or 1,000,000,000,000,000 and you only have a single defect, you ain't at "0-ZERO"

This would be the viewpoint of my customers. I have one customer, who often requests 100% third party sorting when they find even one bad part. I have argued my point several times that "we aren't capable of zero defects". Sometimes they relent and sometimes they don't. But let's just say I do have an excellent relationship with my third party sorting company.

 

[Golfman25]

Let me be perfectly clear, I do not believe in inspecting quality in...but economically speaking, it is sometimes the less expensive option versus designing or error-proofing defects out of the process. As for your molder "a few doors down" I have yet to see an automated inspection system that can deliver zero defects in the molding environment. Today's AI camera systems are coming close, but there are so many potential defects that it's close to impossible to program a camera for them all. Just when you think you've got it, a piece of coring will break that you never thought could! So in molding, automated inspection is typically programmed for the most critical defects, such as a missing insert or a short shot.

Certainly they were not "zero" on all characteristics. Only the ones that matter. This is what was inspected. Zero defects is a fantasy. No process, heck not even the big guy himself, isn't perfect.

 

[toniriazor]

Believing that there is a manufacturing environment capable of producing 0 defects is equal as to believe that Santa Clause will come from the chimney and leave you a present (considering you are not a kid, of course). I think this philosophy was more about making operators conscious about their own work, trying to bring quality mindset in the manufacturing environments and not produce bad parts , that eventually will be caught by quality on final inspection. It is sad, but even nowadays there are manufacturing environments where the workforce (including members from top management) thinks quality is just for the quality department and that this same department is responsible for the quality of the products, which is a nonsense, of course. So "0 defects" was used and it is still used as more as a motivation for the workers to stop producing bad parts and leaving them onto the next process. To me illusory goal / target, no matter the industry.

 

[leftoverture]

Believing that there is a manufacturing environment capable of producing 0 defects is equal as to believe that Santa Clause will come from the chimney and leave you a present (considering you are not a kid, of course). I think this philosophy was more about making operators conscious about their own work, trying to bring quality mindset in the manufacturing environments and not produce bad parts , that eventually will be caught by quality on final inspection. It is sad, but even nowadays there are manufacturing environments where the workforce (including members from top management) thinks quality is just for the quality department and that this same department is responsible for the quality of the products, which is a nonsense, of course. So "0 defects" was used and it is still used as more as a motivation for the workers to stop producing bad parts and leaving them onto the next process. To me illusory goal / target, no matter the industry.

Wait...what? Santa isn't real? Pardon me, I'm going to need a moment here.

We make our operators conscious of performance by offering bonuses for achieving our DPPM goals. And while our goals are lower than most, they aren't zero. It's good to know that we, here on the Cove, all seem to be in agreement zero defects is aspirational but not practical. And who is smarter than the professionals on the Cove?

 

[Randy]

Believing that there is a manufacturing environment capable of producing 0 defects is equal as to believe that Santa Clause will come from the chimney and leave you a present (considering you are not a kid, of course).

Well then who was that I saw kissing momma?

 

[toniriazor]

Wait...what? Santa isn't real? Pardon me, I'm going to need a moment here.

We make our operators conscious of performance by offering bonuses for achieving our DPPM goals. And while our goals are lower than most, they aren't zero. It's good to know that we, here on the Cove, all seem to be in agreement zero defects is aspirational but not practical. And who is smarter than the professionals on the Cove?

Of course, the way to selling mindset 0 defects or less defects goes through the bonus system , there no doubt in that. Recently I read a book of Taiichi Ohno and he is highlighting this as well.

 

[ChrisM]

The problem with zero defects is that it's only zero at the time you check/test for the defect. How many times have you bought something that was DOA, or shipped customers products that were fully tested and working yet when they receive them, they call or email you to say it's DOA ?

However cost effective or otherwise it is to check for zero defects post-manufacture, you never know what's going to happen in the next few minutes/hours. Look at battery-powered bicycle charges and their batteries as an example; hardly a week goes by without another "fire" story in the UK, yet they were all working just fine when they were shipped from the factory

 

[Bev D]

The other thing to remember is that many defects are NOT CAUSED BY THE OPERATOR. In fact in most industries the great majority of defects are physics based and not ‘operator’ based.

 

[leftoverture]

The other thing to remember is that many defects are NOT CAUSED BY THE OPERATOR. In fact in most industries the great majority of defects are physics based and not ‘operator’ based.

True enough, except in the specific cases plaguing me at the moment, at least two are manual assembly jobs where the operator just forgot a step. One of the rejects went through 100% inspection prior to shipping, and the customer still found rejects...and so did we when we sorted our inventory again.