Let me tell straightway that unlike many other technical posts in this site that are based on existing technical facts gained from books, articles, practical experience etc., this particular post is all about my very own interpretation (or definition) of the term “quality”. Since, this is purely based on my view on the term, just put on a critic’s hat and then decide whether to agree fully, partially or disagree. Upto you.
Over the years I have come across plenty of definitions on quality in books, technical documents, the web and so on. Yet, I am not in total agreement with them as they don’t come across quite comprehensive to me. So, I tried my bit to define it myself in a fresh light. Here is what the efforts resulted in.
Quality, in my view, can be perceived broadly in four states or types: Relative Quality (RQ), Planned or Target Quality (TQ), Expected Quality (EQ) and Absolute Quality (AQ). While we keep using the term quality to mean all kinds of standards in a very tentative way, all those actually fall somewhere in or within the four aforementioned boundaries, namely, RQ, TQ, EQ and AQ.
Planned or Target Quality (TQ): TQ is a domain basically for the manufacturers, producers, develpers, creators and of the likes. These are the one who produces, developes or creates something for the consumers, buyers or the users. TQ includes all the virtues a manufacturer, producer, develper or a creator decides to incorporate in it’s product. These are well defined prior to it’s production and while doing so, no approval is necessary from the consumers or the users. If the final product actually possesses the planned virtues or parameters it can be regarded to have achieved it’s quality targets. If it falls short of TQ or exceeds TQ, it is regarded as fairly good, not bad, bad, good, excellent etc. etc. (all relative quality terms) depending on the producer’s perception about the virtues of the product Vs it’s already defined TQ. A producer or developer’s aim should be to achieve TQ as exceeding or not achieving the same may have economic implications. In engineering or construction, TQ is useful for manufacturers of various construction equipment, machinery, materials and so on.
Expected Quality (EQ): EQ is a domain basically for the consumers or the buyers or the users. EQ includes all the virtues a consumer or a buyer or an user expects in a product produced by the producers. Unlike TQ, EQ is not well defined and may vary from person to person. If, in view of a buyer or a consumer the product actually possesses all the virtues or parameters expected by him or her, it can be regarded to have met the EQ requirements for him or her. If it falls short of EQ or exceeds EQ, it may be regarded as fairly good, not bad, bad, good, excellent etc. etc. (all relative quality terms) depending on the consumer’s perception about the virtues of the product Vs his or her EQ. Consumers usually have some sorts of EQs before they go for something. However, EQs can be highly volatile.
Relative Quality (RQ) : Most of the times we talk of quality we actually talk of relative quality. Relative quality of something for a person at any given time is it’s capability of delivering or performing at that particular time (it’s worth or virtues) as understood or perceived by the person, with respect to either it’s target quality (TQ) or the expected quality (EQ) of the person at that time. If the person happens to be the producer or manufacturer of that thing then he weighs his perception about the thing with respect to it’s target quality. But, if he or she happens to be someone else, say a consumer, who is unaware of it’s TQ, then the comparison would naturally be with respect to that person’s expectations (EQ) from that “something” at that particular time.
Since, time keep changing all the time and expectations and perception too may vary from time to time and person to person, the concept of Relative Quality (RQ), or simply quality, too may be different at different times and for different persons.
For example, what is of excellent quality for someone today can very well be of ordinary quality a year later for the same person because of the time factor. On the other hand, what is of excellent quality for someone today can as well be of ordinary quality a couple of hours later for the same person as the person’s expectations (EQ) have drastically changed all of a sudden due to some reason. May be, the person has got much more information about the thing within those couple of hours that changed his perception about it all of a sudden.
Similarly, the same thing can be of different qualities for different persons at the same moment. That’s because all of them have different expectations (EQ) or peception about the same thing at the same moment and so each of them rates it differently.
Theoritically, RQ should vary all the time and for all persons. Practically, it may be the same for several or even many persons. Also, in day-to-day life, the same thing is sometimes regarded as of same quality even after a substantially long time while in reality it’s quality must have changed due to the time factor.
Absolute Quality (AQ): When all the virtues or quality parameters of a product are clearly defined beforehand and both producers (or developers etc.) as well as the consumers (or users etc.) agree upon the parameters formally, these virtues or quality parameters, as a whole, can be regarded as the Absolute Quality or the AQ parameters for the product. If the product possesses all the agreed virtues or quality parameters precisely, it can be regarded as a product of AQ. If it falls short of AQ or exceeds AQ, it may be regarded by one as fairly good, not bad, bad, good, excellent etc. etc. (all relative quality terms) depending upon one’s perception about the existing virtues of the product Vs it’s (already agreed) AQ.
So, whenever the AQ of a product is clearly defined, the goal of it’s producers would be to achieve or slightly exceed AQ as overshooting AQ targets by a big margin may not be economical at all.