Continuously narrow your focus to find the highest leverage area within your chosen field, then go deeper repeatedly

Eben provides a marketing example: 'once you've narrowed, to do it again and to do it again and to do it again. And if you continue this process through your career and you get deep powerful expertise in one area that's a high demand, high value area, this is how you have leverage.' He shows how to narrow from marketing to social media marketing to one specific platform.