Are you referring to the game being a mess at delivering the story? In fairness, that games aren't supposed to be replicas of the book, but rather set in the same style (tactical anti-terrorism and hostage recovery). If the game was supposed to deliver the same story as the book, you're right that it completely failed. I've played almost every game in the series and I've never seen the connection.
Rainbow Six is one of my top-ten favorite books.