I've occasionally gotten into discussions with people about whether or not double opt-in was a bad approach for email subscriptions because it potentially deterred signups. (People would sign up but not click the link in the confirmation email.) My position always was that the people who didn't take the extra step were likely to be less valuable subscribers for the most part, but I was just going by my gut. I never really had evidence--until now.
I didn't realize it, but for years I've been doing what amounted to triple opt-in. My Mailchimp list was set for double opt-in, and my integrations were set for double opt-in. I thought I was just confirming my list settings, but I was in fact making them more complicated. In other words, the integrated providers would confirm the email and send via API to Mailchimp, which would then confirm the email again.
I realized this when I switched to Mailerlite because Mailerlite has an easily viewable list of people who haven't confirmed their email yet. That list got very long very fast, which was worrisome. Stranger, though, was that subscribers from BookFunnel seemed to be getting onto the list without confirming their email. Turns out BookFunnel had designed the Mailerlite integration with their service and sent subscribers to Mailerlite as already active, bypassing the email confirmation. BF did this because it had already confirmed the email.
That was the light bulb moment. I checked my other two providers, StoryOrigin and Gleam (giveaway provider), and both were also confirming emails on their end, meaning I didn't need to have double opt-in set for subscribers sent through API. That was the cause of the huge pile-up of people who didn't confirm their email addressess--they'd already done it and thought they were through.
As soon as I turned off double opt-in, subscriptions started pouring in much faster than before. I had sent my June newsletter to 1,112 people. My July newsletter went to 2,635 people. The absolute number of opens and clicks increased. As a percentage of recipients, however, both dropped. To some extent, that's normal.
More worrisome was the response to my welcome email. On Mailchimp (with a much slower growth rate because of my accidental triple opt-in), open rates were over 50% and click rates over 25% for the welcome email. On Mailerlite, the open rate is 20% and the click rate about 6.5%. It was much higher for the brief period before I removed the extra opt-in step.
There is more than one possible explanation for this data, but the most obvious one is that the people who were willing to jump through the extra hoop were more engaged. Now that it's easier to sign up, I have more subscribers, but the extra ones are largely inert. Over time, that means I'll be paying more for my email list without getting a proportionate increase in interaction. This suggests that, while double opt-in reduces the number of subscribers, it has more affect on the number of unengaged ones than it does on the number of engaged ones.
For those of you who are first building your email lists, there's another take-away. Subscribers gained from people who are subscribing to get a free download of a reader magnet are more likely to interact than people gained from more general giveaways. The difference wasn't as obvious to me before because the extra step that I'd unwittingly inserted was filtering out a lot of the people subscribing to enter a giveaway. Some of the giveaway subscribers were fairly active, so I didn't see as much difference. Now, however, it's more obvious. The groups that open emails and click on links are predominately BookFunnel and StoryOrigin subscribers. There are a fair number of giveaway subscribers who also open and click, but there are a much larger proportion of that population that doesn't interact. (A lot of them lurk on social media and on my website, though, so that they can figure out when the next giveaway is, and some of the ones who don't open emails do share my posts on Facebook. In other words, some people can be good social media followers without necessarily being good mailing list subscribers.)
Summary take-aways:
Don't worry about losing subscribers through double opt-in. Most of the ones you lose will not interact very much.
General giveaways can be a good mechanism to draw people to your site, but they aren't necessarily a good source of subscribers. They work well as a way to reward existing subscribers, but there are better methods for getting new ones.
