Why would a so called "10X" person work 70+ hours? If you think a 10X person is someone who will live at the office you believe in working harder, not smarter

Why would a so called "10X" person work 70+ hours? If you think a 10X person is someone who will live at the office you believe in working harder, not smarter and the other office that hires the guy that works 20hours, but is actually a 10X will run circles around the so called 70+ hours "10X" guy.