Why is regression testing important in the software development lifecycle?

Regression testing is crucial in the software development lifecycle because it helps ensure that new changes or enhancements made to the software do not inadvertently introduce defects or break existing functionalities. As developers modify code, fix bugs, or implement new features, there is always a risk that those changes might impact other parts of the application that are already functioning correctly. Regression testing serves to validate that the existing features continue to operate as intended after such changes have been made.

This type of testing involves re-running previously conducted tests on the updated software to confirm that the behaviors of existing functionalities remain stable. By identifying any unintended consequences of new changes early in the development process, teams can maintain software quality and user satisfaction, ultimately leading to a more robust product.

In contrast, other options do not accurately reflect the purpose of regression testing. Some options suggest that regression testing is limited to checking defects in the latest release or focusing solely on performance issues, which does not encompass its broader goal of ensuring overall functionality integrity. Additionally, it is not a substitute for user acceptance testing but rather complements it by focusing on the stability of previously accepted features following updates.