#17. Kansas City Chiefs, Matt Cassell (2009):
A year after leading the New England Patriots to a 10-6 record in the absence of Tom Brady, the Kansas City Chiefs acquired Matt Cassell to be their starting quarterback. They soon found out the obvious: Cassell looked a lot better when he could throw to guys like Wes Welker and Randy Moss, otherwise he was a below-average quarterback.
In 15 starts in his first season in Kansas City, Cassell lost 11 of those 15 games, throwing as many interceptions (16) as touchdowns.