Market trumps team and product
Paul Buchheit (the original designer of Gmail) agrees with Marc Andreessen that given the choice between a great team, a great product, or a great market, the most important thing is the market.
He also goes on to describe a few examples (Segway) in which brilliant technology development by a great team resulted in failure because nobody wanted it.
I've been through that one myself. But how does a brilliant team with the proven ability to develop great products tune into markets where their work will be valuable? Hmm...