The reason these schemes exist, and the reason so many countries agree to these schemes, is because indeed they see it is to their advantage and to the advantage of their own population. Control over offenders indeed enhances the capacity to manage the risk they pose. That's the reason. It's not because they're bleeding heart liberals that so many countries decided to have these transfers of prisoners. The point was that it was a way to enhance public safety within their country. Accepting transfers allows you to control and to know the offender more and to protect the population better. That's the reason.
The problem here is that this may have been lost in the shuffle, this idea that indeed it's important to bring them back so they can control them. You can accept them for whatever reason, but it's important that they are accepted and come back here.