The idea of confirming permission to send mail to an email address gets a lot of bad press among many marketers. It seems that every few weeks some new person decides that they’re going to write an article or a whitepaper or a blog and destroy the idea behind confirming an email address. And, of course, that triggers a bunch of people to publish rebuttal articles and blog posts.

I’m probably the first to admit that confirmed opt-in isn’t the solution to all your delivery problems. There are situations where it’s a good idea, there are times when it’s not. There are situations where you absolutely need that extra step involved and there are times when that extra step is just superfluous.

But whether a sender uses confirmed opt in or not they must do something to confirm that the email address actually belongs to their customer. It’s so easy to have data errors in email addresses that there needs to be some sort of error correction process involved.

Senders that don’t do this are leaving money on the table. They’re not taking that extra step to make sure the data they were given is correct. They don’t make any effort to draw a direct line between the email address entered into their web form or given to them at the register or used for a receipt, and their actual customer.

It does happen, it happens enough to make the non-tech press. Consumerist has multiple articles a month on some email address holder that can’t get a giant company to stop mailing them information about someone else’s account.

Just this week, the New Yorker published an article about a long abandoned gmail address that received over 4000 “legitimate” commercial and transactional emails.

It turns out that eighteen@gmail.com (let’s call it—him?—“eighteen” for short) had been admitted to a four-year college that features a mascot named Roary the Lion, helped fund a successful Presidential campaign, traded e-mails with a major television network, treated itself to fabulously over-the-top shopping sprees, and, just for good measure, volunteered to work at the PetSmart on 117th Street in East Harlem.

For every email that account received, an actual customer did not receive the email they wanted. Each of those 4000 messages represents a wanted mail not received and a sale not made and an education not received. Those senders, by not doing anything to link the email address to their customer, left money sitting on the table.

Making a clear and direct connection between a customer and an email address is one of the best ways to improve delivery and email ROI. These are real customers. These are people who give a sender an email address. They want that mail! It only makes sense that the marketer would do something to directly link the person and the address. That link doesn’t need to be done just with confirmed opt-in, but all too many marketers delude themselves that their address collection process is accurate. Many of them aren’t doing any data hygiene, and that costs senders real revenue.