What is product quality and how is it determined?
The word quality is defined in many different ways depending on its use:
- Freedom from deficiencies or defects (Juran) - The meaning used by those making a product or delivering a service.
- Conformity to requirements (Crosby) - The meaning used by those designing a product or a service or assessing conformity.
- Fitness for use (Juran) - The meaning used by those accepting a product or service.
- Fitness for purpose (Sales and Supply of Goods Act 1994) - The meaning used by those selling and purchasing goods.
- The degree to which a set of inherent characteristics of an object that fulfils requirements (ISO 9000:2015)- The meaning used by those managing or assessing the achievement of quality.
- Sustained satisfaction (Deming) - The meaning used by those in upper management using quality for competitive advantage.
When we talk about the quality of a product or service we want to know how well it fulfils an expectation or requirement. Does it possess all the characteristics we are looking for in every way? If it does we can say that the product or service is of excellent quality – its perfect. If it falls short in some minor way, we might still say it is of good quality. If it fails to meet our expectations in a major way we would say it is of poor quality. If it is completely useless we would say it is unacceptable quality. Therefore the idea that a product or service is either perfect or imperfect or is or is not a quality product or service does not arise.
We would all like perfection but it is neither practical nor economical. Juran defines quality as fitness for use implying that a product or service is a quality product or service even with imperfections providing it is satisfactory in use. Producers would always aim for total compliance with requirements but a slight imperfection that does not impair use or appearance can be accepted. After all, within 1 year of owning a new car, you might incur a scratch or two on the paintwork, a stain on the upholstery but the car still fulfils your expectations. Would you accept a blemish on a nail, a pack of 100 nails in which two have no heads – it makes no sense to return the purchase to the supplier.
Quality is therefore determined by the extent to which a product or service successfully serves the purposes of the user during usage (not just at the point of sale). Price and delivery are both transient features, whereas the impact of quality is sustained long after the attraction or the pain of price and delivery has subsided.
The inherent characteristics of a product or service created to satisfy customer needs, expectations and requirements are quality characteristics. Physical and functional characteristics such as weight, shape, speed, capacity, reliability, portability, taste etc. If we define all these characteristics in measurable terms and put limits on them we will have defined the standards with which the product has to conform. E.g Instead of saying you want a bicycle that is lightweight (the measure) you need to tell your supplier how light is light weight so you would specify the maximum weight in kilograms (the unit of measure).
See also Quality- what it means