Destination parameter brings you out of the route

Pageroute has an option 'show forward button if destination parameter is set'.

However, one can never set a destination parameter: Drupal will take that destination parameter and forward you there while the pageroute is in action.
say I have three pages:
/pr-register/personal
/pr-register/professional
/pr-register/web

I would expect to be able to say:
/pr-register/personal?destination=user
Then, once I arrive at
/pr-register/web, hitting the [Forward] Button will bring me to /user

This is not the case, because when pressing [Forward] at /pr-register/personal, the first page, I am brought to /user by Drupal already.

did I misnuderstand this feature? Or is it really a bug?