What is Quality?
- Zero defects (Crosby)
- Conformance to requirements (Crosby)
- Fitness for use (Juran)
- Best for customer conditions (Feigenbaum)
Hunt (1992) provides an overview of the defintions of quality. This considers the definitions above a little more thematically:
- Transcendent (you know it when you see it)
- Product-based (defect-free, or presence of required/positive attributes)
- User-based (customer defines needs)
- Manufacturing-based (conformance)
- Value-based (“best for customer conditions”)
Despite the range of definitions, the goals underlying the pursuit of quality and continuous improvement are the same: achieving conformity, reducing variation, eliminating waste and rework, eliminating non-value-adding activity, preventing human error, preventing defects, improving productivity, and increasing efficiency and effectiveness (Okes & Westcott, 2000).
Only one definition seems to capture all of the others, though. ISO 8402 defines quality as “the totality of characteristics of an entity that bear on its ability to satisfy stated and implied needs.” An entity can be any technology – a product, a process, or a system. “Characteristics” covers both the attributes of that technology and the processes that produced it. “Stated and implied” needs acknowledges that customers will have needs, but other stakeholders can have needs too (you, your boss, your shareholders, your company). If “you know quality when you see it,” that means that something is meeting your stated and implied needs – your spoken and unspoken specifications. Even if you can’t define what you mean by quality, when quality is achieved, your implied needs will be met.
As much as the ISO 8402 definition of quality really appeals to me, there is still one framework for understanding quality that’s even more comprehensive and elegant! It’s Mitra’s Model.
Hunt, V.D. (1992) Quality in America: How to Implement a Competitive Quality Program. Mc-Graw Hill.
Okes, D. & Westcott, R. (2000). The Certified Quality Manager Handbook. Milwaukee: Quality Press.