Forgive the defensive attitude here but 2 in 1000 venture backed startups will ever achieve $100-million or more in valuation. is a pretty poor example of "success".
If my start-up made a difference to peoples lives and generated enough revenue to allow me to focus on it full-time then I would consider my start-up a categorical success. Chances are that would happen at a point where my start-up was valued at a significantly smaller figure than $100-million.
Thousands of entrepreneurs would be a lot happier if their focus was a solid, growable, defensible niche business that might never go public or be worth $100-million.
If my start-up made a difference to peoples lives and generated enough revenue to allow me to focus on it full-time then I would consider my start-up a categorical success. Chances are that would happen at a point where my start-up was valued at a significantly smaller figure than $100-million.