Angel investing stands to benefit from economies of scale. Solo startup investing isn’t quite as terrifying a process as solo entrepreneurship, but it still involves the same sort of iron guts and optimism in the face of probable failure. It's your cash on the line, after all. Finding good deals, performing due diligence, haggling with founders over valuation — all can be daunting jobs for a single angel. Getting it wrong means lot of grief and an eventual tax write off.
The wisdom of crowds, especially seasoned, sophisticated crowds, has much to offer in this regard. And that is the basic idea behind angel networks, which boost not only the amount of capital available to an entrepreneur, but also – if done correctly — the intelligence on the other side of the table.