Three years ago, almost anyone could have been an entrepreneur; all you needed was a hot—or even lukewarm—idea. Billions of dollars went into ventures hatched by fresh-faced youngsters with, at most, a couple of years’ experience at pricey consultancies or high-tech companies under their belts. So they had little business experience? No problem; they could always find a grown-up, like eBay CEO Meg Whitman, to handle the operations. Not surprisingly, many young people came to believe that entrepreneurship was a safe career choice. More than a few of their elders, too, underestimated the risks involved in financing start-ups and ended up pouring millions of dollars into doomed ventures.