I follow all of the VCs on Twitter and it's very clear from their many, many tweets that they have a far superior intellect than the rest of us which allows them to divinely predict the future.
And between them and their diverse network of other 40 year old, white males they have a rich, deep understand of the customer's wants and needs. And from that they 'select' the startups that best aligns with this understanding.
I even believe that one day VCs will realise that they don't need founders and can just invest in each other. Keeping the prosperity moving.