So runners are a good example: The runner config is stored in a config.toml on the runner. If you want autoscaling runners, it gets very complex so you might want to version control it or back it up, but you have to store your AWS secrets in this config.toml. It also contains hashes that have to be matched with settings in the UI, and of course, tags, which need to be tied into your .gitlab-ci. UI configuration changes take places instantly and there's no undo. So you have configuration in 3 places, only one of which is version controlled. And lets say you have some new runners with new tags -- you aren't going to be able to run an old pipeline on the new runner.