Hi Mathew,

In MMM 4 I advise users to turn the double opt in off. While I still do this on many campaigns, and usually start my campaigns with it off, I also now advise clients to turn double opt in ON if open rates are low.

I often get reports of people who see open rates as low as 45% on their initial email. This always strikes users as puzzling because it’s hard to imagine that someone might sign up to get free music, but then not bother even opening the email that delivers that music. This is my take on why this happens…

Typically, when I see open rates of less than 65% on the first email it is because people have confirmed opt-in turned off. Doing this is not always a bad thing. However, the reason it can sometimes result in low open rates is because Facebook’s algorithm has become almost a little too good at doing it’s job.

Lets say, for example, that you have created a Facebook or Instagram ad that targets Bob Dylan fans, and that Facebook recognizes 5,000,000 people as being interested in Bob Dylan. And lets also say that the “objective” of your campaign is “conversions” (getting people to sign up to your mailing list). Facebook does not just target fans of Bob Dylan in some chronological order. Instead, the algorithm looks at all of the people that are landing on your designated thank you page (your conversion goal) and creates a segment of those 5,000,000 that most closely match the profiles of those people who are landing on your thank you page. Then Facebook targets that segment, rather than the entire 5,000,000 people.

However, the people most likely to subscribe are the people that have less concerns about handing over their email address. These are often people that have a secondary email address that they don’t check often, or who don’t monitor their primary email often. They have less resistance to signing up because they are not concerned about the inbox clutter. Facebook’s algorithm has become so good at cloning the psychological profiles of people within a segment, that they are effectively cloning the “low hanging fruit” of your target audience. In other words, those who are less likely to check their emails. With confirmation turned off you inadvertently end up feeding the algorithm with these unresponsive, less resistant subscribers, which in turn teaches Facebook to target even more people that are just like them. It;s a terrible cycle that just drives open rates down.

This doesn’t happen 100% of the time that you have confirmed opt in turned off, and there are times that you still want to have confirmed opt in off, but it does seem to be happening more and more. The solution is to make note of your ROI, and then create a duplicate campaign that has confirmed opt in turned on. Track your open rates, click through rates, and ROI separately to see what generates the most overall revenue.

Hope that helps.