Recently, some accredited angel investors have begun moving their investment activity from angel groups, like the Northcoast Angel Fund, to online platforms, like SeedInvest. This decision got me thinking: Will online angel platforms ultimately replace angel groups?

While I don’t think the online sites will drive angel groups out of business the way that digital cameras replaced chemical-film ones, the web platforms will take a sizable number of angels away from groups. Angel groups are better for the very entrepreneurially experienced, active investors who are writing big checks. But the platforms are a superior choice for less entrepreneurially experienced, less-active investors who are deploying smaller amounts of money.

Here are three reasons why:

Successful investing through an angel group takes a lot of time.

Investment success depends on active involvement in screening deals, conducting due diligence, and monitoring investments. Few people have that kind of time. Even experienced and successful angel investors are reallocating chunks of their angel investment portfolios to curated angel platforms because they simply don’t have enough hours to do all the screening and due diligence it takes to make money investing actively through angel groups.

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Few angel groups have enough successful angels to follow.

A few people make outsized returns at angel investing, while most don’t make any money. This distribution of returns creates a dilemma for people who can’t, or won’t, rely on their own judgment.

If you are going to depend on someone else to screen deals, conduct due diligence, and monitor investments for you, as some angel group members do, then you need to follow someone who knows what they are doing. For members of Tech Coast Angels, Band of Angels, or other longstanding angel group with lots of past exits, that’s not a problem. But at many of the angel groups that have been formed in the past decade, less active members are following group managers or active investors who don’t have a successful track record. Those less active investors are probably better off looking on SeedInvest for the companies that Brad Feld, Jason Calacanis,, or David S. Rose are backing, than following someone local who hasn’t got the track record of identifying companies that have exited successfully in the past.

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Once-in-a-lifetime deals aren’t available to members of most angel groups.

Angel groups don’t see many of the really great start-up investment opportunities because those new companies are disproportionately found in places like San Francisco, Boston, and New York. Take unicorns as an example. There aren’t any in Cleveland or Pittsburgh. That means that for angels in most parts of the country the probability of making a seed stage investment in the next unicorn is higher on an angel platform than through a local angel group.

For active angels with a lot of time and entrepreneurial experience, sticking with the angel-group model makes a lot of sense. Group investors are making more informed decisions about opportunities than platform investors because they are meeting the founders face-to-face, conducting due diligence directly, and negotiating their own terms.

But for less experienced and more passive angels who are writing checks too small to get themselves a board seat, migrating to the platforms makes sense. With a platform, the investor can make better use of his or her time, get access to better deal flow, and can more easily follow expert angels.

Angel platforms will not replace angel groups anytime soon. But many inexperienced angels, and angels with little time and limited capital, will move from groups to online platforms. Because those angels make up a large portion of the people who joined angel groups over the past decade, online platforms will change the accredited angel investment model.

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