probably a combination of hard work, sound knowledge, constant learning, creativity and an inspirational personality. He probably had some luck as well but I think the other factors carry a lot more weight.
I am sure he had a plan. Either already lived where that plan was possible or moved there. Did his ground work and made contacts. I can’t speak to his education, but he would need a decent amount of knowledge to be successful. And most likely did some networking to put himself in contact with people who could aid him in his plan.
Hard work pays off. Knowing how to communicate is importaant. And not giving up easily goes a long way.
I agree that hard work pays off. But also making the right connections along the way can either make you or break you. When a trainer reaches a “celebrity class” status, 9 out of 10 times it has to do with being at the right place at the right time or being lucky enough to meet the right people. In my opinion, there is a large number of the so-called “celebrity” trainers who are not any better than the rest of us.