Xmarks is a prime example of why it's better to be lucky than good sometimes. Had these guys bothered to ask for money before simply deciding to pull the plug, they may simply never have raised the necessary funds and gone under like a ship in the night. Perhaps the only reason they don't have to pull the plug now is because they decided to throw in the towel too early, generating loads of buzz and getting their users on board. They tried their best to fail, and fate would have none of it :)