Quality Assurance and Quality Control are two approaches in Quality Management that’s aimed at keeping project processes high and therefore the quality of products and services provided. This is achieved by preventing or removing potential problems in project processes or products, services and systems from affecting stakeholders (Kennedy, 1991).
Quality Assurance is a proactive approach to quality by taking steps to “put good things in” to a project process to prevent potential problems from occurring in the first place. In software testing, test managers employ quality assurance approaches to keep the quality of the testing high and therefore the quality of information uncovered high Common approaches include:
- Hiring practices to find good software testers
- Training and personal development to better train testers
- Test planning and design reviews
- Pair-testing with other testers, developers or business people
- Removing blockers to efficient testing progress
- Advocating for testability in the software-under-test
- Creating or finding tools to help speed up or enable specific tests
Quality Control is a reactive approach to quality by taking steps to “take bad things out” of a project process to prevent potential problems that have occurred from causing harm. In software testing, test managers employ quality control approaches to prevent project stakeholders from being influenced by poor quality information from testing. Common approaches include
- Reviewing test summary or bug reports for false positives or poorly written stories
- Reviewing test summary for further tests or missed risk that could be covered
- Removal of blockers to testing or other project activities
Cost of Quality
The cost of quality is the price of conformance or “doing things right” versus the price of non-conformance or “doing things wrong”. In quality management terms, this is the price of quality assurance and control vs the cost of rework, scrap, warranty, customer support or retesting following the discovery of potential problems (Crosby, 1979).
In software testing, this could be the following:
- Retesting for the same risk, as initial testing was deemed to be inadequate in some way
- Project stakeholders spending extra time on bugs due to low quality reporting
- Testers rewriting test summary of bug reports to bring them up to standard
- Project stakeholders spending extra time to fix bugs that would have reasonably expected to be found by usual testing approaches
- Not reporting blockers, issues, constraints or risks that slow down testing or project activities
- Crosby, P.B. (1979) Quality Is Free: The Art Of Making Quality Certain. 1st Ed. New York, NY: McGraw-Hill, pp. 119–126
- Kennedy, L.W. (1991) Quality Management Nonprofit World: Combining Compassion and Performance to Meet Client Needs and Improve Finances 1st Ed. San Francisco, CA: Jossey-Bass, pp. 61–80.