Disagree. No matter how lucky you are. No matter who you or your family knows. If you give up quickly because you lack patience and/or grit, you are very unlikely to still be successful. How many startups succeed or become "unicorns" without at least a single pivot? Precious few. IMO grit is not the only factor of a successful person, but it sure as heck is one of the most common things you'll see in a successful person. A few examples.
Elon Musk, first generation immigrant, didn't come from money, is now a billionaire. An article was released this week interviewing Mr Musk where he plainly states he put his desk at the end of the assembly line in th Hawthorne Tesla factory. He then went on to mention how he has a sleeping bag and often sleeps there.
One of my favorites is to look at how many awful failures Abraham Lincoln went through. It would have broken most people, yet he soldiered on and ended up being one of the most important Presidents in US history: www.abrahamlincolnonline.org/lincoln/education/failures.htm
Virtually everyone on HN knows how much of an obscene work-a-holic Steve Jobs was. He was also a first generation Syrian immigrant. Luck? He was fired as CEO from Apple before founding Pixar and NeXt. He still refused to give up. Grit doesn't mean being a work-a-holic though, it simply is extreme perseverance.
This inability to fail but sheer willpower is called grit. You're underestimating the power of raw unadulterated willpower if you take things outside of your comfort zone and to the extreme. Those people did, and your great grand children will likely hear their names.
Yet another take on Mark Cuban, Richard Branson, and Larry Ellison. The common thread in every one of these stories is grit, the inability to accept failure at face value and continue on until you succeed.
www.inc.com/minda-zetlin/how-mark-cuban-richard-branson-and-larry-ellison-failed-spectacularly-before-bec.html