Quality

Quality has two main definitions in dictionaries: first the "way of being, good or bad of something", example: the quality of a land. It is then simply opposed to "quantity", without any notion of value. The land can be good or bad; the second meaning is "superiority, excellence in something", example: a quality fabric. A certain hierarchy is then introduced: a quality fabric is better than the others. This is the top of the line. But practice has imposed a third meaning: the object or service that fits well, that has no flaws, for example: a practical, reliable, easily washable vegetable press that does not make too much noise. The notion of hierarchy is however excluded: there may be several levels of vegetable press quality, with more or less sophisticated functions, with prices of course accordingly. All are of quality when they have the characteristics advertised. Quality is then opposed to defect. A quality object is an object without flaw, that is to say one that meets its specifications and, more generally, the expectations of its users. And this extends to services and organizations: a supplier is of quality if he delivers on time, has a rapid after-sales service… A dyer is of quality if the clothes are properly cleaned (without residual stains…) . What we measure are in fact the defects observed in relation to our expectations (what we will call "non-quality" below) ...