Dr. Gottman said, "Like the second law of thermodynamics, which says that in a closed energy system, things tend to run down and get less orderly. The same seems to be true of closed relationships like marriages. My guess is that if you do nothing to make things better in your marriage, but not do anything wrong, the marriage will still tend to get worse over time."

Essentially what he's saying here is if you want to overcome this natural drift that will pull you apart over time, you have to do more than just not screw things up...