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What is quality 6

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25362

Chemical
Jan 5, 2003
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Although quality is easy to talk about in generalities, it's difficult to define in specifics.

It was Aristotle who said: "Quality is not an act. It is a habit."

Think for a minute what quality, or the lack of it, means to you, objectively as well as subjectively, and let us learn from your opinions.
 
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My brother is a carpenter and a perfectionist. He is always spending too much time a job's money, but refuses to leave a job until its "perfect".

Once he was lamenting that he spent so much time on fine details of a job, that he made only 4 per hour at the end. I said there is a difference between doing a $2000 job for $500 vs. giving a person the best $500 job possible for $500.

The point: perfectionism is not quality.

[bat]I could be the world's greatest underachiever, if I could just learn to apply myself.[bat]
-SolidWorks API VB programming help
 
Well quality is defined in ISO 9000 as reaching a stated failure rate (something which is often forgotten by managers who insist that all vendors much be ISO 9000). So if you state that you aim for a maximum failure rate in a component of 98% on post manufacture testing is OK, and you achive 97%, then you've got a quality manufacturing process...

For me quality is "doing what it says on the tin"- it is a cheap and cheerful one shot disposable product that does the job once, for example. Or the guy that tells me I can get a rough draft by friday and produces a report by the deadline that has good technical content but lots of spelling errors, poor formatting and no pictures has produced a quality piece of work.
 
For me, quality is how well something meets (or exceeds) my expectations (which sometimes change with time just like any customer). This is a purely subjective measure unless I have made those expectations known up front. If the expectations are known and accepted, you at least then can establish an objective measurement of quality. From there you can attempt to influence or control it.

Lack of quality simply to me means problems.

Regards,
 
This was a significant topic in the 1980's. One cheer leader was Phillip Crosby. His definition of quality was conformance with the requirements.

This is big. In other words, if you need basic transportation, then an inexpensive but reliable car is a quality car. A Mercedes or BMW exceeds your requirements. A used Mustang may be just fine.

This is big because you must define your requirements in specifications, references to applicable codes and standards, detailed drawings, etc. Specify that something must work. This seems basic but is not.

For the QA departments it is all about documentation and procedures. QA may not care whether something works so long as quality procedures exist, proper material documentation exists, the paper trail is suitable.

John
 
Some thoughts, for what they are worth.

"Quality" is, of course, relative, much like "fast". A quality product is one that is superior to, or at least equals that of your competitors.

Quality, these days, appears to be very closely aligned to "continuous improvement". So, in DrillerNic's example above, 98% may be satisfactory in year 1, but might not be in year 2.

Quite often, quality implies that a certain minimum or required standard has been reached. Improvements beyond this that have a cost implication may prove to make a company uncompetitive.

The 'Quality triangle' indicates that there is a direct correlation with cost and time.

Finally, a company or product with the word 'quality' in the name is usually missing the word 'poor'. "Quality speaks for itself."
 
For an interesting read on quality and its elusive definition, read ZEN AND THE ART OF MOTORCYCLE MAINTENANCE by Robert Pirsig.
 
Concerning the posts I've read in the meantime, I'll transcribe herebelow some paragraphs from an article I had the chance to read on this subject.

...A goal of zero errors or defects may be the only way. Jeff Dewar of QCI International once said:

If we accept 99.9% as our goal, we'd have to accept the following conditions:

[•] 2 unsafe plane landings per day at O'Hare airport
[•] 16,000 pieces of mail lost by the USPS every hour
[•] 22,000 checks deducted from the wrong account
every hour
[•] 20,000 incorrect drug prescriptions each year
[•] 32,000 missed ehartbeats person per year

That puts quality goal in perspective. Thus perfection should be the aim every way every day...

...Speaking of products an services, there is no need to be a prophet to predict that in the years ahead, technology won't win the war. The competitive difference in industry wil be the people who attend to quality.

Would anyone like to comment ?
 
25362
Quality is how well something fits your specifications.
Chevrolets and Mercedes Benze cars have equal levels of quality, Godiva chocolate and Hershey bars have the same level of quality.
They all have different standards and specification but they all were made to meet those standards.
A Rolex and a free watch from Burger King have the same level of quality. The pilot on your next airline trip will probably not be using a Sponge Bob watch made in China. Both watches met the standards of quality for the markets they were made for.
Higher standards usually cost more. Were willing to spend the money to prevent accidents at O'Hare but if your kids Sponge Bob watch is 10 minutes off per day, who cares.
You might want to read thread 765-98263. IMO it was a clear example of not having a standard and in turn not getting the quality for the ruquired job.
 
Wow, 61 bpm AVERAGE over a yr; now, that's quality!

Being in systems engineering, I'd like to warn everyone to not get hung up over specs. As with pornography, you know it when you see it, but defining it is a tenuous proposition.

> Most customers haven't a clue how to specify what they want, so specifications are sometimes irrelevant to the actual operational requirements of the product

> Writing a good specification is tricky. All requirements should be quantifiable and testable

> But, requirements verification can be like a science project. No one might have enough money to pay for verifying systems with complex requirements.

> Case in point, military systems generally have specifications that include sections with environmental conditions and reliability requirements. An exhaustive verification of a million-dollar system against ALL its environmental and reliability requirements could cost $25-million and more than a year to cover the all the units that are destructively tested and labor/facilities required.

Personally, I'd define quality as a product that works in the intended application and exceeds customer expectations.

Down with software that deny the possibility of working in any intended application!

TTFN
 
BJC
The examples you listed may be true as far as the manufacturer is concerned, but how individuals perceive that "quality" is much different. You forget to mention that "quality" is a highly subjective term. I would definitely prefer the Mercedes, Godiva chocolate and a rolex watch over the alternatives, if I could afford them. Why? Because, to me, they are of higher "quality". For example, high quality chocolate will melt in your mouth very quickly. Hershey chocolate has to be masticated a bit (or left in a warm place) before it will melt, and even then it doesn't compare. The feeling of a high quality chocolate in your mouth is something you will not experience with the waxy confections made by Hershey.
 

BJC, I read thread765-98263 which dealt with lawn mowers and ended with specifications, and you know what they say about that: An elephant is a mouse built to government specifications. Building elephants seems to be a very unprofitable product line...

From the standpoint of the manufacturer, as John L. McCaffey said: "... You have to make some stuff and sell it to somebody for more than it cost you. That's about all there is to it,...except for a few million details."

So, it appears that quality should be nothing but... continued attention to details. True?

 
The question that eludes many companies is, "which details?"

Consider WalMart and K-Mart, similar names, similar businesses. K-Mart has been dying a slow death and WalMart has more clout that some countries.

The second issue is that some of the details are conflicting. Is it even possible to make something perfectly safe? If so, can it even be built or sold at a reasonable price? Does the customer even care; since he probably is more interested in sharpness and durability in a knife than its safety?

TTFN
 
The classic answer to the question of "what is quality?" is it is very hard to define, but you know it when you see it.

A lot of replies here regarding reject or failure rate.

When you aim for perfection, do you actually achieve it?

What would you expect to achieve if you aim for less than perfection?

Several replies regarding meeting expectations (specifications).

If I ask you to provide me a product that fails to perform as intended 76% of the time, requires twenty hours of maintenance for each hour of use, and, when it does work, 50% of the product produced must be rejected and you provide me exactly that, have you provided a quality product?
 
ewh
Once you decide what charesterics a product should have quality is not subjective. A Hershey bar may be good enough for a break at work but not good enough for your sweety on her birthday. Godiva has higher standards that result in better chocolate, maby they use only fresh milk and Hershey uses powered, maby Godiva uses only cocoa from Ghana grown at elevatons of 1000 meters and Hershey may use cocoa bought on the spot market. Godiva is better is better because they have higher standards for every ingredinet and step in production.
Getting quality on a project is a matter of writing tight specifications and seeing that they are delivered and installed they way want. The use of the project is a key factor in the specifications. If your doing the electrical system in a K-mart it not as tight as the electrical system in a data center. The K-mart the Hershey, the data center is the Godiva. On "9" is OK for a K-Mart, you need 6 "9"s for a data center.
Sometimes conditions or circumstances may force you to make a product or process that conformz to standrds that are nearly impossible, thats when engineering gets fun.
 

Quality: One of the most misused and misundersood words in the English language. The level of quality must be quantified for it to mean anything. For example, the phrase "We manufacture and sell a quality product" to most people means that it is a good or reliable product. The manufacturer however, ommited to say that it was a product of poor or average quality due to the level of quality control.
Let's say we have two widget factories manufacturing the identical product....same method of manufacture, same material etc., both flying their ISO 9000 certification banners. To get certification, they "say what they do and do what they say" and later, the ISO auditers are satisfied that they are meeting their requirements. The difference being that factory A randomly inspects 10 out of 100 widgets. Factory B on the other hand, inspect 100% of theirs, scrap the deficient ones and only perfect widgets go to market. This of course having a vast difference in the cost of the widgets.
As defined in the American Heritage dictionary, quality is "An inherent or distinguishing characteristic; a property."
Widget A has the distinguishing characteristic of failing and widget B has the distinguishing characteristic if lasting a lifetime.
So, the word quality on it's own means nothing.....it's the level of quality that either satisfies or irates the customer and the higher the level the better which means basically, you only get what you pay for. Like the Chevy and Mercedes example.

Haggis
 
BJC,
I agree with you to a point. You are stating what quality means to the manufacturer. Once defined, all of the product that passes QC is of quality.
As haggis stated above, quality means nothing if not quantified. Both Hershey and Godiva sell quality products. It is up to the end user to decide what level of quality they desire and are willing to pay for. It is in that sense that I feel that quality is subjective.
 
BJC,

Your example is of infant death. Given your premise, A and B have identical operational behavior. Once all the DOA widget A's are dealt with, the remaining product behaviors are identical.

This is what's called "initial" quality in the automotive industry, which works great if you junk your car every 2 years.

However, for those who keep their cars, the supposed additional quality of B does not really exist, since the initial screening only captures infant failures

TTFN
 
IRstuff
I think you explained my Pontiac.
A and B cost the same to make?
If your specing lug nuts for a car, do you buy to a loose spec and sort out the bad ( achieving quality by inspection is never a good or workable solution ) or you can just put them on the and car let the lawyers tell you there bad.
Do peoplse still read Demming in the auto business?
Does the Firestone for SUV tire thing sound like a quality problem or an inspection problem?
 
MintJulep, I'm not sure if your example is taken from real life, but I can think of real products that are successful that have each of your quality limits individually.

"If I ask you to provide me a product that fails to perform as intended 76% of the time,"

This is failure to perform during the mission. 76% might be an acceptable failure rate where the product depends on a scattergun or bulk property - eg microballoons as fillers in resins. Filtering systems might only be 24% efficient, per stage. But with enough of them you can build atomic bombs. Another class of example would be where the performance of the vital few is of far greater impact than the majority.

" requires twenty hours of maintenance for each hour of use,"

Modern fighter planes, or torpedoes, would easily exceed this

" and, when it does work, 50% of the product produced must be rejected and you provide me exactly that,"

One example might be a tyre and wheel balancing machine. I'm not sure if 50% is a reasonable estimate of the number of wheels that need a second go, but it must be of that order.

" have you provided a quality product?"

If those were sensible and compatible customer defined specifications, then I believe, yes, it is a quality product. The last one is the most interesting, since the high reject rate has an enormous effect on the manufacturer's costs, yet with 100% testing, it has no effect on the customer. At the same time this is not regarded as an acceptable solution where I work, since any failure of the inspection process will result in poor product. There's also the question of how exactly the pass mark is set - how sure are we that a 49th percentile part is a failure in the cutomer's eyes, and a 51% is satisfactory?




Cheers

Greg Locock
 
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