" The true challenge is how you continue doing it, after you’ve ridden the biggest wave, crossed the longest distance. You set up challenges that are more than what you
ever did before. And by getting through it, you get the sensation you’ve completed something. And if it’s dangerous, then other things that scare you, the experience will strengthen you for those situations. "

― Steven Kotler , The Rise of Superman: Decoding the Science of Ultimate Human Performance