Git merge behavior (ahead of x by y commits) -

i've came across git behavior cannot understand. repo used tens of people. case this:

$ git checkout master $ git merge --no-commit feature automatic merge went well; stopped before committing requested  $ git status on branch master branch up-to-date 'origin/master'.  conflicts fixed still merging.   (use "git commit" conclude merge)  changes committed:      modified:   web/webapp/grails-app/views/layouts/empty.gsp  $ git commit -m 'commit message' [master e6cc2eb] commit message  $ git status on branch master branch ahead of 'origin/master' 21 commits.   (use "git push" publish local commits) 

what confuses me part:

your branch ahead of 'origin/master' 21 commits. 

how come it's not 1? make clear, there single change in empty.gsp file.

there 20 more commits, why not show after git status? hints might missing?