The marginal cost per customer is not that different if it's a small customer or a massive one, so it's much interesting for you to go after the big ones that w

The marginal cost per customer is not that different if it's a small customer or a massive one, so it's much interesting for you to go after the big ones that will generate much more revenue. You miss out on revenue from smaller customers, but your margins are higher (and it's totally possible that the revenue from smaller customers isn't financially directly worth it, if the support costs around them are too much). Of course that skips the bigger picture like more people knowing and using your products and being happy with them leads to more champions for them doing your sales and marketing work for you, which can create lots of revenue in the long term; but it's pretty much impossible to quantify.