So take a notepad and write down what you consider as your motivation for the behavioral change. Write them all down. If, based on what you have written down, you decide to move on with the habit change, keep the list because it will come in handy on those days when you are feeling down and need some motivation. All you would need to do is to take a look at the list once again to be reminded of all the reasons why you need that habit change and why you decided on it on the first place.