In his new book, Tribe of Mentors, productivity guru Tim Ferriss asks over 100 high achievers for their top life tips
You are the average of the five people you associate with most.
Why the world's top performers always avoid the number seven | Wired
tl,dr It's a matter of choice, your in or your out of something. Picking outside of the acceptable makes you choose NO or Heck Yeah! Like Derek Sivers intends.