Each year, the National Hockey League hands out a "general manager of the year" award. It's rather silly.
Judging an executive on a team's single-season success is a rather myopic assessment of overall effectiveness. For example: Ray Shero won the award in 2013 for the Pittsburgh Penguins. He was fired in May 2014. Over the course of one season, a general manager might sit upon a throne of unparalleled accomplishments; but after a few bad trades and even worse luck on the ice, that same general manager can have his bottom planted firmly on the hot seat.