At the end of the day, it's virtually everything.
If you examine the role of the judge—and the judges have at least privately, if not publicly, lamented this—you see that they are rubber stamps. They don't have a judicial function. They don't weigh the evidence. They don't make determinations of reliability.
I know of very few ministerial decisions—perhaps one or two—in which the minister declined to surrender after a decision was made on extradition. Maybe I'm being too general in that answer.