Success and significance is relative and it is important that you see why it is so. I don't know where you are from but opportunity is a big part of the story. A majority of the world does not have the same level of opportunity as the western world. Being in the bay area, being born with the right passport, being around with the right people, right education etc are really big influencers of success and have nothing to do with individual itself.
This is not to take away anything from what many people like PG have done, but it is for you to realize that sometimes lots of energy is spent by other people just trying to achieve basic things which are usually taken for granted.
As an example, I wanted to travel on a business trip to this country. My partner could go immediately because he didn't need a visa. My visa processing is still stuck and it's been a week now. Lost opportunity and no amount of hardwork and perseverance from my side can fix it. yeah, this is part of the reason that I am writing this comment. I feel terrible about my passport :)