Quality assurance focuses on avoiding problems and defects when delivering products of services to customers. ISO 9000 defines this as part of quality management focused on providing confidence that quality requirements will be fulfilled (ISO, n.d.). ITSQB defines quality assurance as "Activities focused on providing confidence that quality requirements will be fulfilled." (ITSQB, n.d.).
Although often used as synonym for Quality Control, quality assurance differs due to its process orientation. It targets prevention of defects and continuously improvement of the delivery cycle. Focussing on quality earlier in the process, a.k.a. shift-left. The goal of quality assurance in the software development lifecycle is to develop products that meet specifications and customer expectations. In other words is the act of guaranteeing the customers that the delivered product fulfils their preferred quality level.
Advantages of quality assurance are significant:
ISO. (n.d.). ISO 9000:2005(en) Quality management systems — Fundamentals and vocabulary. ISO Online Browsing Platform. Retrieved 12 October 2021, from https://www.iso.org/obp/ui/#iso:std:iso:9000:ed-3:v1:en
ITSQB. (n.d.). ISTQB Glossary. ITSQB Glossary. Retrieved 12 October 2021, from https://glossary.istqb.org/en/search/quality