🌁Software Engineering: Cost of Quality [CoQ] (Definitions)

"Cost of poor quality is the cost associated with providing poor-quality products or services. There are four categories: internal failure costs (costs associated with defects found before the customer receives the product or service), external failure costs (costs associated with defects found after the customer receives the product or service), appraisal costs (costs incurred to determine the degree of conformance to quality requirements), and prevention costs (costs incurred to keep failure and appraisal costs to a minimum)." (Laura Sebastian-Coleman, "Measuring Data Quality for Ongoing Improvement ", 2012)

"A method of determining the costs incurred to ensure quality. Prevention and appraisal costs (cost of conformance) include costs for quality planning, quality control (QC), and quality assurance to ensure compliance to requirements (i.e., training, QC systems, etc.). Failure costs (cost of non-conformance) include costs to rework products, components, or processes that are non-compliant, costs of warranty work and waste, and loss of reputation. " (Cynthia Stackpole, "PMP® Certification All-in-One For Dummies®", 2011)

"Costs incurred to insure high quality and/or the actual and opportunity costs from problems with poor quality. Also see quality-related activities." (Leslie G Eldenburg & Susan K Wolcott, "Cost Management 2nd Ed", 2011)

"Money spent during the project to avoid failures, including prevention and testing costs. COQ operates on the premise that costs for meeting quality requirements are less than those for dealing with nonconformance to requirements." (Bonnie Biafore & Teresa Stover, "Your Project Management Coach: Best Practices for Managing Projects in the Real World", 2012)

"All costs incurred over the life of the product by investment in preventing nonconformance to requirements, appraisal of the product or service for conformance to requirements, and failure to meet requirements." (Project Management Institute, "A Guide to the Project Management Body of Knowledge (PMBOK Guide )", 2017)

"The total costs incurred on quality activities and issues and often split into prevention costs, appraisal costs, internal failure costs and external failure costs." (Software Quality Assurance)