How can people who have been able to rob the state for millions of dollars go unpunished?

I think that when a person breaks the law and steals a large amount of money, then he takes care in advance to have a place where he can hide from the representatives of the law. Usually, criminals choose countries where there is no extradition (for example, Mexico) or another country as a safe place where he lives with fake documents (this is what Ilya Surkov, a Russian economic fraudster did). When I first found out about this, I was very surprised that he chose London as his safe place from punishment for a crime, but I was even more struck by the fact that he continues to break the law and can escape from justice again.