It comes down to if you have a rating system that only uses W/L and not margin of victory, there's two options:
1) a system where wins always moves your rating up even if against bad teams, and losses always move you down, an example is the Elo rating system
2) a system where losses to good teams is sometimes viewed more favorably than wins against bad teams, RPI is an example
The problem with the first is when a team has control over it's schedule, it can be advantageous to not play many good teams and improve your rating by loading up on cupcakes. The RPI isn't perfect but it has had a positive effect on college BB scheduling overall and is generally reasonably accurate by the end of the year.