Because he built his core audience, catered to them for years and they followed him and bought into his success with their money and support.
He used the money he made to build a better infrastructure to keep his machine moving and never stopped.
Instead of asking for Hollywood for help, he continued to work and grind and made his own Hollywood.
He studied the craft and business, used what he learned and implemented it in his business practices.
He's also very creative and has a great mind for creativity. That creativity and the means to create and actually produce a product will make you very successful.