When the Facebook IPO flopped, we all learned something we probably should have known. Don't buy an IPO, particularly a social media one that warns about the desktop-to-mobile transition in the public filings most people never read on its first day or even its first week or first month. Allow some dust to settle. I'm not sure what we, as smallish individual investors, could have hoped to learn from Knight. For one reason or another, from time to time, we actually experience this roller coaster that is the stock market. Go figure. From all four of these "debacles" (Enron was, Facebook not so much, Knight gets an "I don't think so" and Google an "um, definitely not"), we learned two primary things, relevant to life and investing. People make mistakes. Sometimes they're criminal. Sometimes they're negligent in some other way. Sometimes they're just crappy decisions that hurt lots of people. Sometimes a machine "makes" a person do something dumb. Sometimes good old, completely innocent human error comes into play. Clearly, based on Larry Page's comment that somebody hit send early, we can assume human error deserves responsibility for the leak. That should put most of the hysteria to rest. Somebody made a freaking mistake. Pardon this small aside. Please don't yelp because Google didn't act fast enough to explain what happened or because they might have possibly though we're not really sure given analysts a heads up on earnings. That never happens (picture that little emoticon where the yellow guy rolls his eyes). And, while I'm at it, I won't mention his name, but somebody on television (bald guy with a cool pony tail) needs sensitivity training for ripping Page's lack of "enthusiasm" on the conference call. We have no idea what's wrong the guy, but it doesn't sound good. We should laud him for even showing up. We also learned that there's risk in investing, particularly in stocks. Big time. It absolutely stuns me that we're not desensitized by that reality by now. Given all of the atrocities we accept on a daily basis -- gang murders, war in the Middle East -- it's somewhat shocking that we can't live with risk in the stock market.