What @poVoq said.
Even simpler: every time you push
a commit to a repository (or open a Pull request, or add commits to a Pull request), CI/CD will:
- Run automated tests to make sure everything is fine.
- Run autoformatters and similar program (optional).
- Build binaries for a number of platforms.
Having such an infrastructure makes testing easier (although I prefer to do it locally). Having binaries for Linux/Win/Mac to distribute or give out to testers is tremendous if your compiler is not top notch regarding cross compiling.