One is when one is not dependant on what one is.
For example, if you are called brave, and the situation arises that requires bravery, you can't depend on your title as "Brave" to pass the requirements; rather, you need to be brave at that very moment, regardless of what you were before, or what you are going to be after. By depending on being brave, one can't show signs of bravery. Likewise, by depending on being rich, one can't show signs of richness, or depth, in character.