Principles are ways of successfully dealing with reality to get what you want out of life.
Ray Dalio, one of the world’s most successful investors and entrepreneurs, cites principles as his key to success.
A proper goal is something that you really need to achieve. Desires are things that you want that can prevent you from reaching your goals. Typically, desires are first-order consequences. For example, your goal might be physical fitness, while your desire is to eat good-tasting but unhealthy food. Don't get me wrong, if you want to be a couch potato, that's fine with me. You can pursue whatever goals you want. But if you don't want to be a couch potato, then you better not open that bag of chips.