He wasn't given anything. Winchell was (and is) a business, not a charity. The article lacks details but Ockham's Razor dictates that the most plausible was t

He wasn't given anything. Winchell was (and is) a business, not a charity. The article lacks details but Ockham's Razor dictates that the most plausible was that Winchell and he entered into a business arrangement where he was running their donut shop for a share of profits. They provided the capital, he did all the work and Winchell got a cut of his profits. He then saved aggressively and started buying more donut shops. Notice that Winchell had similar arrangement with many other people and presumably they didn't become millionaires. As to luck: he trained 100+ other immigrants to successfully operate a donut shop so if an immigrant that most likely doesn't even speak English can profitably operate a donut shop, maybe luck is not such a big factor. As for why he became a millionaire and not others - I don't see any luck there either. He followed the same formula a hundred times: open one more donut shop. He was just more ambitious, worked harder, saved more aggressively and took a bit more risk.