What should be done frequently with changes on user story and defect branches before merging?

Verifying changes on user story and defect branches before merging is crucial to ensure that the code being integrated into the main codebase is functioning as intended and adheres to project standards. This process helps in identifying any bugs, conflicts, or unintended side effects that might arise from the new changes. By performing thorough verification, such as unit testing, code reviews, and integration testing, teams can maintain the quality of the software and reduce the risk of introducing issues into the mainline.

Other approaches like deleting branches or archiving them are more about managing code rather than ensuring quality during the development process. While pushing changes to the mainline is a necessary step, it should only occur after the verification process confirms that everything is ready and safe to integrate. Therefore, prioritizing verification reinforces good practices in software development, leading to a more stable and reliable codebase.