Fuzzy and relative concept of quality

Definitely the concept quality and its understanding are most essential matters of quality integration and quality management. However, it is not easy to cope with this central concept. In ordinary every-day language quality may mean many different things. Also its professional interpretation is fuzzy and relative.

The international standard vocabulary ISO 9000 defines quality as: degree to which a set of inherent characteristics fulfils requirements This definition implies many interesting aspects:

• Item to be addressed from the quality point of view should be defined. Very often this item is a product (goods or service) produced by an organization, but the item in a quality consideration may be any kind of object.
• All items have a lot of inherent characteristics, and quality of the item is squarely depended on them.
• Fuzziness relates to the degree that the item possesses particular characteristics and through them fulfils certain requirements.
• Requirements consist of all needs and expectations of all the interested parties related to the item. These requirements may be general or specific, stated (explicit) or implied (implicit and non-articulated), or any kind of combination of them. Therefore the requirements are never completely a priori unambiguous or objective. One should always recognize the perception of all interested parties in order to get impression about the quality of the item.
• Fulfilling requirements often means that the interested parties get satisfied or they get benefits or value using the item.

Too often – unfortunately – in practice quality concept has intermingled with the concept grade. Quality is subjective and grade objective concept. ISO 9000 defines grade as category or rank given to different quality requirements for the items having the same functional use. Examples include class of airline ticket and category of hotel.

In the contexts of quality considerations there are often also needs for concepts of non-quality. Correspondingly to quality and grade quality practices have adopted the following two terms:

• Defect – non-fulfillment of the needs and expectations
• Nonconformity – non-fulfillment of the stated requirement specifications