According to the document, research shows that by adulthood we have heard the word "no" over 400,000 times, far more than the word "yes". However, many people still fear rejection, as evidenced by the author's own fear of hearing "no" when starting their networking journey. The document encourages reframing conversations by thanking people for their honesty and asking to follow up in the future, rather than perceiving a "no" as rejection.