Actually, doesn't that prove that having a co-founder is as important as pg argues? You need co-founders for moral support as much as anything. Having your co-f

Actually, doesn't that prove that having a co-founder is as important as pg argues? You need co-founders for moral support as much as anything. Having your co-founder leave puts you in a bleak situation; it kills morale. Not to mention there were probably external factors about their business and market that lead them to believe more and more that they picked the wrong idea or executed "poorly". Having more "passion" as a single founder doesn't really make you better off or more likely to succeed. IMO, its a buzzword, because everyone wants to be successful and will claim they have dieing "passion", but at the end of the day all that matters is results. What I think happened here: They picked the wrong market/idea or executed poorly. They weren't seeing results they wanted; they lost morale. Eventually one of them figured out it wasn't going to work out, didn't believe or have the patience to iterate their idea and decided to leave. The startup was finished. This is probably what happens to 99% of failed startups.