A startup can easily take 10 years from funding to the point where it's purchased or no longer needing more investment.
My first business was founded in 1995 before being sold (for decent money - e.g a successful outcome) in 2011. Was the business still a startup after 10 years? I would argue yes. There were still many ups and downs, funding challenges, near-death experiences etc, and our culture was still largely that of a startup business.
Even if you consider the massive tech IPOs and classic success stories, the timeline between incorporation and IPO is pretty long. Microsoft was founded in 1972 and IPO'd in 1986. Google took 9 years from incorporation to IPO, and it was 8 years from Zuck launching 'thefacebook' until the Facebook IPO. I think this backs up Sam's assertion that a startup is a 10 year commitment for a founder.
Even if you consider the massive tech IPOs and classic success stories, the timeline between incorporation and IPO is pretty long. Microsoft was founded in 1972 and IPO'd in 1986. Google took 9 years from incorporation to IPO, and it was 8 years from Zuck launching 'thefacebook' until the Facebook IPO. I think this backs up Sam's assertion that a startup is a 10 year commitment for a founder.