Sometimes, if you remove something large from a Git repository, it will leave a bunch of data in the .git directory. A good example is if you run a git reset command to reset the repository back to a previous commit and you don't care about the data from all the commits after the commit to which you reset. You can remove the unused objects in your repository by the running the two commands below.

git reflog expire --all --expire=now
git gc --prune=now

Be careful, though, because you can't undo it!