Another problem with Facebook is that the very qualities that made it so successful as a private firm could sink it as a public one.Facebook says in its IPO papers that it's not about to rein in the sort of rebel culture at the company that has encouraged "innovation" just to deliver "short-term" profits that please Wall Street investors. If only "short-term" profits were the only demand. When you go public, you are promising investors that your profits will not only rise, but do so consistently, quarter after quarter, in predictable increments. It's a fiction. The nature of many businesses is such that profits come in messy lumps. But companies exploit loose accounting rules, as Wall Street expects them to do, to make their profits seem smoother than they really are. Is Facebook not going play this game, either? That would be admirable. And disastrous for investors. I suspect what's got people in a lather about Facebook is that they think it could become the next Google or Amazon. Those stocks went public at high earnings multiples, and still managed to reward investors handsomely. But the bulls forget the big role played by happenstance and luck in business success, and how difficult it is to separate winners from clunkers ahead of time. And there have been a lot of clunkers: ICG, Priceline.com, Pets.com, Netscape and, more recently, Pandora Media, Demand Media and Groupon. The stocks of those latter three are down more than a third from their IPOs last year. Maybe this is just a matter of taste. I prefer the dowdy and obscure over the hot and well-known. But I think there's another distinction here. Facebook is a gamble, a fun fling, like buying a lottery ticket. The valuation is just too high, the unknowns too many, to call it an investment. If you're going to sink money into the company, recognize that much at least.