You are what you call yourself

I've done plenty of fitness programs and lifestyle eating programs that call for a rigid 6-day eating plan with the 7th a 'cheat day' where you can eat anything you want.  The only thing more harmful for your longtime fitness goals than calling this a cheat day is calling it a, "you're a piece of shit day."   You are what you call yourself.  So if you call your plan (and by extension yourself) a cheat long enough, your system starts to believe it can only succeed by being dishonest.  And then you cheat on your cheat day because your system thinks you're already dishonest so what's the harm?  Your system literally self-sabotages your actions so they match what you say about yourself and eventually the wheels fall off the truck and you're shotgunning ice cream sandwiches while watching Wheel of Fortune reruns on a Wed.   

You need that 7th day to give your willpower a chance to recharge.  Call it a free day, me day, eat day, or Sunday.  Anything but a cheat day, because it's not.