Metrics Mayhem: What's Causing Subscriber Complaints?

When first confronted with an elevated complaint rate, many email marketers react with Fear, Uncertainty, and Doubt, often citing reasons why users should not be moving their mail to the spam folder. “These users opted-in to receive the mail I send them,” or “My emails contain information that’s valuable to my customers,” are just two common objections.

This “FUD” is understandable since email marketers develop sophisticated strategies and expend countless resources to acquire subscribers who then unexpectedly mutiny and move messages to spam. Each time a user moves one of your messages to spam, their mailbox provider will register a complaint. Since complaints are usually looked at by mailbox providers as part of an overall complaint rate for your IP address (# of complaints divided by overall volume received), it’s important to keep complaint counts low and inbox placement high.

So why are these users, who may have once shown enthusiasm for your brand, now complaining when they receive your content? They signed up willingly and are now moving everything you send to the spam folder, to your detriment! Well, the truth is that subscribers are only human and as we know, people can change their minds, behave illogically, and lose interest in things they were once excited about.

The good news is that you can adapt to these changes by planning for them and making sure that you’ve acquired high-quality subscribers in the first place. It’s time to examine the user experience of your email program to create a positive experience for your subscribers. Taking preemptive steps to design user touchpoints can directly affect how users feel about your email program and is critical to preventing them from complaining.

List acquisition: Who are your users?

The first thing to do is identify the entry points to your email program to determine where your subscribers come from. If you’ve been following our blog, you might have already taken heed of our warnings not to purchase lists from third parties. Purchased lists can be riddled with spam traps or unknown users and generally create more headaches than they’re worth. This is worsened by the fact that the users behind those email addresses will not be expecting you to email them, increasing the likelihood of complaints. The highest quality subscribers are those who have signed up through a clearly branded entry point (like the sign-up form on your website) and have given express permission for you to email them after reading clear disclosures on your send frequency and content. This high level of familiarity with your brand makes these users less likely to complain and increases the likelihood that their email addresses are valid.

IP address segmentation: Handling unavoidable risks
What if your business policies require you to send to individually purchased leads? Or if you collect email addresses at the point of sale in your retail stores? Or if your users have privacy concerns and often make up email addresses? Depending on where your subscribers come from, you will need to associate a certain level of risk for each entry point to your email program. First, judge the level of risk based the likelihood that the user’s email address is invalid. Consider typos, made up email addresses, and how long it’s been since the user signed up. Next, consider the likelihood that the user will be surprised to hear from you or be unfamiliar with your brand (both lead to complaints).

To manage this risk, you should mail to riskier audiences on specific IP addresses dedicated for risky traffic, separate from any IP addresses that send mail to your engaged subscribers (subscribers who have opened, clicked, or purchased recently). This protects engaged subscribers from having issues in receiving your mail due to a poor sender reputation, thus protecting your ROI. This practice also allows you to monitor deliverability and sender reputation independently from your designated risky IP addresses. Further IP address segmentation can give you visibility into which acquisition points are delivering good results and which could use more attention.

User lifecycle: Adapting to your users’ changing mindsets
Once you’ve segmented by risk level, review your user touch points starting with your sign up form: Users should be made aware of the following when they share their email address:

  • The fact that they are signing up for an email program
  • The type of content they will receive
  • The frequency with which they will receive this content. Next, implement a welcome series.

Your welcome series is a series of initial emails meant to guide users from the sign up form to your regular email program. It’s essential that your email templates are on-brand to ensure users recognize who you are and remember why you’re sending them mail. In your first email, you should thank users for signing up and reiterate the expectations you set in your signup form. In subsequent emails within your welcome series, introduce users to your brand, product, or tools.

What happens when users are no longer in the market for your offering or have lost interest? In this case, it’s best to avoid bombarding them with deals. Instead, opt to share content that shows you’re a thought leader in your industry, like a newsletter. Adapting to your user’s changing mindsets will allow your brand to stay top-of-mind without losing relevance or creating annoyance.

With this in mind, consider implementing a preference center where users can calibrate your email program for their own needs (perhaps by switching to a seasonal newsletter instead of a weekly update). Even then, it’s likely that some users will just stop opening your mail. You should identify these unengaged users, then send a message to gauge their interest in future communication.

Win-back campaigns: Checking in on unengaged users
In the email industry, we call these win-back campaigns. You’ll recognize these in your own inbox as messages that have subject lines like “We miss you!” or “Is everything alright?” In these emails, the sender mentions that they’ve noticed you’ve stopped opening their mail and asks if they did something wrong: Did they send you irrelevant content? Did they send to you too frequently? Are you simply no longer interested? The goal here is to get unengaged users to open this last message with an eye-catching subject line, then have them reaffirm their interest, adjust their preferences in the preference center, or unsubscribe. If the user doesn’t respond, you should suppress them from your list. This saves you the trouble of mailing to unengaged users who could potentially turn into unknown users (users who have abandoned their email accounts) or recycled spam traps (email addresses once used by users that have been repurposed by mailbox providers to catch bulk senders who don’t care about engagement.. The largest mailbox providers factor engagement (opens, clicks, forwards) into their filtering algorithms, so it’s best to avoid mailing to unengaged users.

Feedback loops: Handling unavoidable complaints
What if your users complain anyway, despite your best efforts to introduce them to your brand and to present the value of your email program while being sensitive to their changing needs? First, take into account “brand exhaustion” which is when a user hears from you simultaneously through voicemails, text messages, push notifications, social media, and email. Users sometimes complain on emails as a way of expressing frustration when you have overwhelmed them with messaging from other channels. 

Mailbox providers take complaints as an indicator that your content is unwanted. You should also take this approach. In fact, as a bulk sender, most mailbox providers will expect you to process these complaints and suppress complainers from future sends. Many major mailbox providers offer a feedback loop (FBL) for this reason. When you sign up for a feedback loop, mailbox providers will send data about complaints that they receive on your mail in an industry standard format called ARF (Abuse Reporting Format). The expectation is that you or your ESP will take advantage of this data by programmatically suppressing users in response to these FBL complaints. Taking this step will help ensure that users will not have to complain more than once to stop receiving your mail. This in turn reduces the pool of users in your list who are likely to complain on future campaigns.

Security and authentication: Protecting your hard work
Let’s now assume that you have a basic user lifecycle established. You’re working hard to provide valuable content while giving your users flexibility when their needs change. As a result, your users respect your brand and have invited you into their inbox with open arms. With great power comes great responsibility! Your users’ brand affinity and your good sender reputation are both assets that allow you to use email effectively as the high ROI marketing channel that it is. It’s important that you protect these assets because spammers, spoofers, and fraudsters are all eyeing them.

The good news is that email authentication technologies have evolved dramatically over the years and bulk senders have more ways to protect both themselves and their users than ever before. So make sure to take advantage of the industry-standard authentication methods available. This means you should implement SPF, DKIM, and DMARC and check your SMTP servers for open relays (mail servers that anyone on the internet can send through). Also consider leveraging a tool like Return Path’s Email Fraud Protection to keep an eye on potential attacks. Once an attack is discovered, Return Path can connect you with a takedown vendor who will help stop bad actors from impersonating your brand. 

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