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.
Think of people's performance as being made up of two things: learning and ability, as you'll see below. A weakness that is due to a lack of experience or training can be fixed, while a weakness that is due to a lack of ability can't be. Failing to distinguish between these causes is a common mistake among managers, because managers are often reluctant to appear unkind or judgmental. Also, they know that people assessed this way tend to push back. This is another one of those situations in which you must force yourself to be practical and realistic.