Email List Hygiene

6 Reasons to Treat Inactive Subscribers Like Zombies

minute read

zombie_on_computuer_w1024 (1)As consultants for Return Path, we’re occasionally called in when deliverability or ROI has been massacred.  Regularly, the issue can be traced to a high population of inactive subscribers, unknown users and spam traps.  While the zombie thing has just about been run into the ground, it’s truly one of the best ways to describe the issue with inactive subscribers.   In this post, I’ll cover 6 ways that your email program has more in common with The Walking Dead (and wider zombie genre) than you realize.  Don’t worry… I won’t include any spoilers.

1.To Email Receivers, You are the Unknown, and the Unknown is Dangerous

We’ve seen it time and time again in the genre.  Once you have a safe zone, you need to be very, very selective with who you let in.  Similarly, email receivers are wisely distrustful of anyone sending large scale or commercial emails.  They are protecting their populations and will almost always run the risk of being too careful with suspicious mail instead of not careful enough.

Microsoft, AOL, Gmail and Yahoo all use subscriber engagement to determine whether your mail lands in the inbox, the junk folder or gets blocked completely.  If you show up at the gateway leading a bunch of zombie subscribers who aren’t engaging with your email, you look like a potential threat and you’re likely going to have a problem (as shown in this post).   From their perspective, your subscribers aren’t interested in your mail and you don’t appear to take your list hygiene seriously.   The higher your percentage of inactives, the worse your email program looks.  Think of this as the equivalent of being the sketchy character with the shifty eyes who is looking for shelter and may or may not be alone.  You’re just not setting yourself up for success with this approach.  When working with clients, we use Return Path’s Inbox Monitor to keep a finger on the pulse and determine just how sketchy our clients look to email receivers.

Your Inactives can “Turn”

Think of your inactives as zombies that have limited mobility or are missing limbs.  They are less lethal but still bad news, especially if there are a lot of them.  You’re basically tempting fate by having a bunch of these around.  What a lot of marketers don’t realize is that this scenario can actually escalate without fair warning.

There are various reasons that a subscriber goes dark.  They may not need your products or services any more, they may not like your offerings or emails, or they have completely abandoned their email account.  If they have given up on their inbox, it’s only a matter of time before they turn.   If this sounds ominous, that’s because it is.  At a certain point, email receivers stop recognizing users who have abandoned their accounts.  This is when your inactive subscriber turns into an unknown user.   That slow, lumbering zombie now looks a lot more menacing to email receivers.   This means that you have subscribers that are so old and dead that they are no longer recognizable.  Again, not a great look for your program if you want to make it in to the inbox.

The good news is that unknown users are still fairly easy to identify and take down.  Just make sure that your bounce handling process is suppressing these subscribers.  It’s essential to get rid of these folks.  They are never coming back to life.  If they do suddenly disappear from your bounce logs, they have turned into something far scarier: A recycled spam trap.  This is basically a deactivated email account that the mail receiver has brought back to life with the sole purpose of lying in wait for you to mail to them again.   Think of this as the zombies hiding out of the shadows waiting to attack you from behind.  When you mail to these traps, your deliverability is most likely going to take a hit and your placement is going to suffer.

If you’re using Return Path’s Reputation Monitor, you’re basically working with night vision.  Having a view of your unknown user rates and spam traps across your IPs can help immensely but do keep in mind that awareness is only the first step towards correcting the problem.

3.Your Zombies can Create More Zombies

Let’s say that you keep your inactives on your active email file, hoping that some of them will come back to life and open their wallets.  What you should realize is that these zombie subscribers don’t have to do any biting to infect more of your list.  All they have to do is prevent more engaged subscribers from seeing your mail.  Let’s say you’re getting bulked at Gmail due to low engagement.  If subscribers aren’t rushing into their junk folders to rescue your mail, inactivity is spreading.  If they forget about you (yes, this happens) or start shopping with your competitors instead, they may be joining your growing zombie herd in the near future.   If you are sending all of your mail off of one IP or you have a block of IPs that you round robin, this is an issue that could hurt the performance of even your best subscribers.

Now don’t start thinking that this post if the equivalent of the guy on the street corner with the sign that says “The End is Near.”  Below are the things you can do to save the good subscribers on your list.

Quarantining Your Zombies  Can Protect Your Healthy Population

If you are totally opposed to ridding your list of zombies (this is a bad idea) or you want to keep the majority, consider quarantining them.   As I mentioned earlier, your inactive subscribers are the slow, lumbering types.  This makes them easy to track down.   Once you’ve identified them, you can corral them on one IP address.  This will help ensure that your most engaged, living and breathing subscribers get your mail and have the opportunity to take action.  I should warn you that the IP you use is likely going to have some trouble.   You can experiment with the inactivity threshold you use for banishment to this IP to help even out performance.  At least your healthy subscriber population will be protected.

5.Once They Show Signs of “Infection,” Act Quickly!

There is hope for some of your zombies, but like The Walking Dead, you have to be swift and intentional with treatment for it to work.   Once a subscriber shows signs of inactivity, the quicker and more relevant your response, the better your chances are of saving them.

One approach that may help reduce your inactive rates is to shift efforts up in the lifecycle, targeting subscribers just as they begin to disengage.   You have a much better chance of saving a subscriber if you catch them when they are still among the living on your list.

If your re-engagement efforts are set to kick in after 1 year or more of inactivity, most of those subscribers are pretty much already doomed.   Think of this strategy as your last ditch effort.  You may have a few folks come back to life but don’t expect this type of program to be your cure all for inactivity.  For all re-engagement (and early re-engagment efforts), be sure to test your content, offers and subject lines to drive heightened response.

6. Sometimes Subscribers Just Can’t be Saved

If your policy is to keep your zombies around for years, it’s only a matter of time before it comes back to bite you.  Whether on the screen or in your database, it’s always a hard decision to turn your back on those you’ve worked hard to keep alive.  Unfortunately, in both the zombie genre and in email marketing, sometimes this is the best option.  I understand that you’ve worked hard to build your list.  Your number of subscribers is a prized metric.  The problem is that the zombies on your list could be killing your deliverability and holding back the performance of you program.  In the long run, clinging to that higher list number could result in lower ROI.

Whenever possible, cut your dead weight and get rid of subscribers that haven’t engaged with your program in an extended period of time.  Mail receivers have different thresholds for when they start putting up the barricades, usually ranging from 6 months to 1 year.  If you are having deliverability problems, the mail receivers are already suspicious of you and you may need to get more aggressive in dispensing your inactives so receivers know that you are taking your zombie problems seriously.  This post provides a nice overview of how to identify inactives without gettting ruthless with your cuts.