It's hard to explain in writing, because I can't talk about it in person. Stats are meaningful and do show things, but they aren't the tell all. For example, what if a QB throws for 300 yards, 3 TD's, and only 1 INT but that INT cost his team points, or he fails to score on his final drive to win the game. Then the opposing QB only throws 215 yards, 2 TD's, and 1 meaningless INT but wins the game based on being smarter in certain situations. The 1st QB will have a higher Passer rating and QBR which is where it is flawed. I can come up with 100's examples like that.