I didn't say anything about motivation. That sort of hardship
redefines the failure threshold.
For most people, who have never had their expectations reset, cramming your whole family into a rented studio apartment and eating mainly ramen and beans and rice might be considered a failure. But in comparison to fleeing halfway around the planet to avoid being murdered for no good reason, it's only the smallest possible success.
When you know that whatever you do, the worst that can happen is that you drop back down to the minimum level of success, you can take more risks. You can start a business, then lose it due to market changes and go back to regular jobs, like in the ancestor post.
Some people never take that risk, because in order to start that business, they would have to put their own retirement fund or their kids' college funds on the line. It never occurs to them that having their kids hunted down by partisan thugs to be killed is worse than having to take out student loans. Their failure threshold is higher.
Your grandparents wouldn't say that. They might say that you take all the great things you have for granted, and that even if you lost most of them, you would still be a success by their definition. And it wouldn't just be because they're your grandparents. It would be because about everyone you encounter in your daily life has a 2000 kcal diet, clean drinking water, flush toilets, high rates of public vaccination, multiple channels of broadcast radio and television, a very broad range of rights that are usually respected, usable public transportation in most cities, and tax-funded public education all the way up through high school.
Even if you lose absolutely everything you own, you can still get all that, with little more effort than putting up with some bureaucratic hassle or some religious preaching. As long as you are not literally insane or a professional criminal, it's not tremendously difficult to just survive in any American city.
So they already provided a better life for themselves and their families. If you can visit a family on public assistance in subsidized housing and still tell yourself that it is better than failing in your country of origin, you can risk every last penny you have on your business, right up until it goes bankrupt, because in America, that's as bad as it gets for anyone willing to follow all the rules.
It isn't just immigrants that take advantage of that lower risk threshold. There are plenty of non-immigrant hustlers that come out of poor areas with their low-investment businesses. Most of their business is technically illegal, such as selling homemade tamales for cash out of your uninspected home kitchen, and not reporting the income. Or selling bottled water in heavy traffic on a hot day. Or braiding hair in your apartment without a beautician's license. Those businesses cannot grow past a certain point, because they usually can't invest in fixed capital or hire employees, but they still exist. And every so often, you get John Paul DeJoria, or Harold Simmons, or Larry Ellison, or Howard Schultz, or Oprah Winfrey.
http://www.theatlantic.com/politics/archive/2015/03/welfare-...
http://www.washingtonpost.com/news/wonkblog/wp/2015/03/26/wo...