Welcome to the Forum.
First, your transition is setting the stage for what will happen at some point. The Revision Numbers tab should say what Rev scheme your using, that is all. This isn't where the Rev is being set, or stamped, however, and you can verify that in the History of the file (RMB from WE in a folder view). You see this again in most cases in the State that follows next. That is where the "stamp" goes; hence the "1". If you were to take away the Rev scheme in the State, you would notice it disappears from the transition. It's really just a confirmation.
There are so many ways to build workflows, and depending on how you configure it, these don't always "feed" into one another in perfect order; what I mean is, the transition with the Actions doesn't always immediately precede the State that Stamps the Rev. They can be separated, depending on what your Workflow is doing. That's a little more advanced than the Default workflow. Which, by the way, when you set up a new workflow, having a "Default" workflow to use as an "example" is a great way to keep yourself in check.
Hope this helped!