The only thing worse than getting a low response rate to an e-mail campaign is to see a rise in the number of recipients who unsubscribe. Why do customers defect? We’d like to think it was unrelated to our business, but that's not always the case.

We’ll take a closer look at why customers opt out of your e-mails and the benefits of being unceremoniously dropped (yes, there are benefits). And we'll talk about what you can do after they’ve left.

First, let’s explore why customers hit that dreaded Unsubscribe button. With as unbiased a view as possible, consider the following questions.

• Did you test the campaign on a small group before you went big? If you did test it, what were the response rates? Did you see variations in those responses in terms of demographics, social sharing and forwarded e-mails?

• Did you segment your audience based on their interests? On an analysis of how they’ve responded to previous communications, campaigns and offers?

• What was the timing of your e-mail? More specifically, how often have you reached out to your subscribers?

• Did your e-mail focus solely on a generic offer or did it balance information and education with a relevant and compelling offer?

Ideally, the answers to those questions give you insight into how to strategically plan your next campaign.

So where’s the silver lining in losing subscribers?

First, it enables you to learn what types of messages and offers are most effective with your audience segments. Examine the pass along and social-sharing results of those who did respond to your campaigns.

Second, it allows you to more effectively engage with your most ardent supporters. By further identifying your fans, based on interests, responses and VIP status, you can create more customized messages and offers that appeal directly to their needs.

Now what do you do when some of your raving fans decide to opt out of receiving your messages?

This doesn’t necessarily mean they’ve abandoned your business. They may continue to support you by purchasing goods or providing solid word-of-mouth recommendations. If they do, then opting out of your messages may indicate that your e-mails aren’t in sync with the customer’s buying experience.

You can improve this feedback by asking customers what they’d like to hear about. You can also learn more by seeing which goods are sold most often. Check which products sold together and what sold most frequently. And track common customer questions. Use this knowledge as the basis for your next e-mail.

While "unsubscribe" may at first appear to be a negative, it provides valuable insight. It helps small businesses evolve their marketing campaigns and get higher response rates.