Quality
From StudyWiki
Overview
Quality is a complex concept with many different facets. This makes it difficult to define as different people emphasise different aspects of it. To understand the different ideas behind the term quality, it helps to understand the different concepts behind the term software quality assurance
People forget how fast you did a job - but the will always remember how well you did it
—Howard Newton
Definitions of Quality
- Software Quality
- The degree to which a system, component, or process meets specified requirements
- The degree to which a system, component, or process meets customer or user needs or expectations
Conformance [...] to implicit characteristics that are expected of all professionally developed software
—Pressman, Software Engineering: A Practitioner's Approach, European Edition, 5th Ed. Page 198
- Fitness for purpose (Juran)
- Conformance with specified requirements (Crosby)
- Quality as a multidimensional concept:
- speed
- performance
- reliability
- security
- ease of use
- etc
Your definition of quality depends on who you are and your perspective:
- Developers may define quality in terms of functionality
- Managers may define quality in terms of cost
- both may include reliability and usability in their definitions
- as both factors contribute to product's image
Five Different Views on Quality
- Transcendental View
- Quality is a concept that is impossible to define, but some products have it and some don't. We will recognise it when we see it.
- User View
- Quality is concerned with user satisfaction
- Product View
- Quality is something that can be determined by measuring aspects of a product's performance: speed, reliability, ease of use, and similar aspects.
- Manufacturing View
- Quality is the result of a rigorous and well organised development process: a high quality process leads to a high quality product
- Value for Money View
- Quality is a measure of how much a customer feels that the product was worth the money they spent on it
