Testing has become an integral part of Drupal development but often it's often only focused on technical aspects and implemented at the end of the project lifecycle.
Shift left testing is the process of moving the testing phase left of its usual position in the delivery pipeline so that it occurs as close as possible to the build process. By proactively testing integrations early and often, you can isolate most defects sooner for faster remediation, resulting in more efficient projects with higher quality.
Continuous Collaboration is a software delivery approach in which organizations work seamlessly together across technical and non-technical departments. The approach aims to reduce the friction inherent in software development projects by aligning with an organization's decision making processes and by allowing non technical stakeholders and team members to contribute and give meaningful feedback on a day-to-day basis. As with CI and CD, CC also ensures that any changes or features that have reached the end of the process can be deployed.