Software quality assurance economics

ContextSoftware companies invest in quality assurance in order to lower software development and maintenance cost, and to increase revenue and profit margins. To contribute to increase of net income, a quality assurance organization has to consider cost and value of the testware involved in assuring quality of software artifacts, such as requirements, specifications, designs, and code.ObjectiveThis paper proposes a set of economic metrics: testware return on investment, inflation, and cost and value sensitivity to artifact changes and time passage. The paper proposes a set of guidelines on lowering testware cost, on increasing value, on maximizing return on investment, and on when to release.MethodThis paper presents an industrial case study data on the relation between test case cost and value, and on cost and value sensitivity to time passage and artifact changes.ResultsThe industrial case study showed return on investment on test cases of up to 200%, deflation of up to −2% per month, undesirable economic effects, such as test case cost outpacing test case value and rapid test case value depreciation based on time passage.ConclusionA viable QA organization should measure and improve test case return on investment, inflation, and cost and value sensitivity to artifact changes and time passage.