If you're playing by the rules, it includes any scenario where a Git repo is stored within Dropbox.
Git expects to have full control over the files in the git repo. Git does not expect any changes to the files that it does not perform itself. Any scenario where an outside process performs regular changes to the Git repo is an opportunity to corrupt the repo.
Git expects to have full control over the files in the git repo. Git does not expect any changes to the files that it does not perform itself. Any scenario where an outside process performs regular changes to the Git repo is an opportunity to corrupt the repo.