Config file does not list newly created branch

I know there are 2 ways to create a branch. Remotely using a gui version control like GitHub or locally using git bash. When I create a new branch remotely and fetch the changes using git bash, the new branch is listed in my config file in the .git directory.

However, when I create a branch locally using git checkout -b <branchname> it is not listed in the config, but when I check its creation using git branch -l it is listed as it should be. Why is this? It is only after I specify the remote counterpart for the local branch that it is listed in the config.

I have created a new branch using git checkout -b <branchname>. I expect at least the [branch "branchname"] entry to appear in the config file, but nothing appears.

There is a known feature of git checkout [name], when [name] does not exist yet locally but exists on a remote:

-- from git help checkout:

If <branch> is not found but there does exist a tracking branch in exactly one remote (call it <remote>) with a matching name and --no-guess is not specified, treat as equivalent to

$ git checkout -b <branch> --track <remote>/<branch>

The added section in .git/config comes from the --track <remote>/<branch> part, not from the fact that you create a local branch.