How should you treat your best customers?

Here's what most businesses do with their best customers: They take the money.

The biggest fan of that Broadway show, the one who comes a lot and sits up front? She's paying three times what the person just three rows back paid.

That loyal Verizon customer, the one who hasn't traded in his phone and has a contract for six years running? He's generating far more profit than the guy who switches every time a contract expires and a better offer comes along.

Or consider the loyal customer of a local business. The business chooses to offer new customers a coupon for half off—but makes him pay full price…

If you define "best customer" as the customer who pays you the most, then I guess it's not surprising that the reflex instinct is to charge them more. After all, they're happy to pay.

But what if you define "best customer" as the person who brings you new customers through frequent referrals, and who sticks with you through thick and thin? That customer, I think, is worth far more than what she might pay you in any one transaction. In fact, if you think of that customer as your best marketer instead, it might change everything.