This is the beginner’s mind. When you are a novice, you do not know what you do not know. Then, when you become a master, you do not know what you know. In between when you reach the stage when you know what you do not know, and then, when you know what you know, is critical. Most people fail to achieve mastery because when they reach the stage where they know what they know, they become egoists, and starts viewing the world as an oyster. The price is that, they never become masters but by then it does not matter.