Have you ever heard of it?
Even if you haven't I would be willing to bet you have gone through it!
Here is the Diet Cycle (let me know if this sounds familiar ;)
You are starting a new diet, this is going to be the one! You are pumped! You are excited! You are motivated because this time will be the time that you finally get it together, that you finally lose X pounds, that you finally kick your sugar addiction! You have your workouts scheduled, your meals planned, your family is on board to support you! Yup, you've got this and you are going to kill it!