I would say they did everything right except choosing to build an e-mail client. The days of paying for e-mail clients is long gone. The days of even using a local mail client are over for most people. It's just a tough sell to make money selling a paid client to a free service. I use Sparrow and will continue to use it but I can understand why they were going to have difficulties making any real money off it. Way too small of a market.