You see, in life, lots of people know what to do, but few people actually do what they know. Knowing is not enough! You must take action.
In essence, if we want to direct our lives, we must take control of our consistent actions. It's not what we do once in a while that shapes our lives, but what we do consistently.
What we can or cannot do, what we consider possible or impossible, is rarely a function of our true capability. It is more likely a function of our beliefs about who we are.
One reason so few of us achieve what we truly want is that we never direct our focus; we never concentrate our power. Most people dabble their way through life, never deciding to master anything in particular.