Ask Successful People of HN: What influenced your personal growth the most?

I want this directed at those that have a net worth of at least $3 million. While that's by no means a definition of success, my question is geared towards achieving financial freedom.

Assuming many of you were once at a stage where you knew little about starting a business, striking deals, and leading a team, what, in your opinion, are the most influential books, quotes, stories, etc, that contributed greatly to your development into a person fit for success?

Swombat wrote a comment here a few weeks ago in which he said "successful companies come out of successful people", and from that point on I've been thinking about how one would become a successful person, or in other words, how one would prepare oneself to increase the chances of being in a position to lead a successful business. I thought it'd be of great value to me and others here if we heard from financially successful people of this community on what they credit as being the main reasons that helped them grow into being "successful people".

Books, anecdotes, a mentor's advice on everything from personal improvement to business mechanics are welcome.