Sometimes the product itself is a kind of distribution.

ZocDoc is a company that helps people find and book medical appointments online.

The company charges doctors a few hundred dollars per month to be included in its network.

With an average deal size of just a few thousand dollars, ZocDoc needs lots of salespeople—so many that they have an internal recruiting team to do nothing but hire more.

But making personal sales to doctors doesn’t just bring in revenue; by adding doctors to the network, salespeople make the product more valuable to consumers (and more consumer users increases its appeal to doctors).

More than 5 million people already use the service each month, and if it can continue to scale its network to include a majority of practitioners.