What are the drawbacks of a double opt-in process?

A double opt-in process seems like a practical solution to avoid sending to bad addresses. If you require subscribers to respond a second time to confirm their registration, the likelihood that they’ll hit the spam button diminishes, right? The problem is that it doesn't always work that way, and can have some negative consequences to list growth.

With some estimates of double opt-in failure rates ranging as high as 50 percent, marketers should implement such a program with great care and caution. In fact, only two of the 175 companies evaluated in Silverpop’s “2005 Retail Email Study” used a double opt-in process to confirm registrations.

So, why do so many recipients fail to complete the double opt-in process? Here are some possibilities:

• The actual confirmation email isn't sent out immediately. By the time someone receives a confirmation, the person has forgotten all about signing up or has decided he or she no longer wants to be on the newsletter list.
  
• The recipient doesn't recognize the "From" field. In the past especially, a lot of double opt-ins would come from auto-responder systems that didn't allow the brand of the actual marketer to be displayed. So recipients would get a strange message and be unsure of what to do with it.
  
• Recipients have been trained never to click on anything in a message. Some email recipients are so concerned about phishing and Internet security that they are hesitant to click on anything in an email--not even a link to verify their permission.

All these reasons impact response rates of a double opt-in process. Additionally spam filtering can keep confirmation emails from reaching inboxes, thereby cutting the double opt-in process in half. The bottom line is that malicious users, aggressive spam filters and poor execution can combine to make double opt-in a problem.