What are some surprising truths about email marketing?
Matthew Whittaker
Co-founder & CTO, Suped
Published 1 Jun 2025
Updated 19 Aug 2025
6 min read
Email marketing is often perceived as a straightforward digital channel, perhaps even a relic from an earlier internet era. Many assume its rules are set, its efficacy declining, or that it is simply a matter of sending out messages. However, the reality is far more nuanced, filled with unexpected complexities and surprising truths that defy common assumptions.
The landscape of email marketing is constantly evolving. What was true yesterday may not be true today, and what works for one sender might fail for another. Navigating this dynamic environment requires a deep understanding beyond surface-level metrics and conventional wisdom.
From regulatory misconceptions to the subtle art of inbox placement, there are many aspects of email marketing that can catch even seasoned professionals off guard. These surprising truths shape how successful campaigns are built and delivered, making it crucial to stay informed and adaptable.
The unwavering ROI of email
One of the most surprising truths is that email continues to deliver an exceptionally high return on investment (ROI), often outperforming newer digital channels like social media. Despite the rise of other platforms, email remains a powerful tool for customer acquisition and retention.
Many marketers are astonished to learn that email marketing generates, on average, $36 for every $1 spent, according to studies. This remarkable ROI highlights its continued efficacy in a crowded digital landscape, making it indispensable for businesses of all sizes.
The direct nature of email communication allows for highly personalized and targeted messaging, which resonates deeply with subscribers. This one-to-one interaction is a key factor in its enduring appeal and ability to drive conversions effectively.
Hidden deliverability hurdles
A common misconception is that using certain words in subject lines, such as 'FREE!!!', will automatically trigger spam filters. While it is true that excessive use of capitalization and exclamation marks can be a red flag, the mere presence of words like 'free' does not guarantee your email will go to the junk folder.
Another surprising truth related to compliance is that the CAN-SPAM Act, the primary US law governing commercial email, does not actually require opt-in. It focuses more on providing an opt-out mechanism and accurate sender information. This is often a shock to those who assume all email regulations mandate prior consent.
Deliverability is a complex beast, and simply sending emails in plain text does not magically bypass spam filters, nor does including a footer stating the message 'can't be considered spam'. Inbox providers evaluate numerous factors, including sender reputation, content relevance, and recipient engagement, regardless of formatting or self-declarations.
Common belief
Email delivery is mostly about avoiding obvious spam trigger words and sending to a clean list. If your email isn't in the spam folder, it's considered successfully delivered.
Surprising truth
Email deliverability goes far beyond the spam folder. For example, a common issue with Gmail deliverability is 'tab mis-placement' where emails land in the Promotions tab instead of the Primary inbox. While not 'spam', this can significantly reduce visibility and engagement, making it arguably worse for marketing outcomes than ending up in a junk folder that users actively check for missed emails.
Authentication isn't the only answer
While email authentication mechanisms like SPF, DKIM, and DMARC are critical for establishing trust and improving deliverability, they are not a silver bullet. Even with perfect authentication, your emails can still face challenges if your sender reputation is poor.
Sender reputation is built over time based on factors like engagement rates, spam complaint rates, and whether your IP or domain is listed on any email blocklists or blacklists. Being on a blocklist (or blacklist) can severely impact your ability to reach the inbox, even for legitimate mail.
For instance, if your domain is listed on a blacklist (or blocklist), it signifies a trust issue with mailbox providers. It is not just about the technical setup, but also about the history and quality of your sending practices. Managing and monitoring your reputation is an ongoing effort that is crucial for sustained deliverability.
The true meaning of engagement
For years, open rates have been a cornerstone metric in email marketing. However, with the advent of privacy features like Apple Mail Privacy Protection (MPP), the accuracy of open rates has become significantly skewed. This means that a high open rate might no longer truly reflect user engagement.
Data shows that mobile opens account for a significant percentage of all email opens. Therefore, the impact of MPP, which pre-fetches images (and thus triggers 'phantom' opens), cannot be overstated. Marketers need to look beyond raw open rates and prioritize more reliable metrics.
Instead of obsessing over potentially inflated open rates, focus on metrics that indicate genuine interest and action. These include click-through rates (CTR), conversion rates, and unsubscribe rates. A low click-through rate or a high unsubscribe rate, even with a high reported open rate, signals an underlying problem with your content or targeting.
Metric
Traditional View
The surprising truth
Open rate
Indicates how many recipients viewed your email. High is always good.
Privacy features (like Apple MPP) can artificially inflate open rates, making them an unreliable indicator of actual engagement. Focus on other metrics to see why open rates are increasing.
Unsubscribe rate
A high unsubscribe rate is always bad, indicating poor audience fit.
While high rates are concerning, a steady, low unsubscribe rate can be healthy, indicating your list is self-cleaning and retaining truly engaged subscribers. Abnormally high opt-out rates can signal other issues.
Spam complaints
Any complaint is a critical failure and a sign of bad practices.
While serious, even legitimate marketers can receive occasional complaints. The key is to monitor trends using tools like Google Postmaster Tools and aim to keep rates below industry thresholds to avoid significant reputation damage.
Mobile optimization is not just a best practice, it is a necessity. More than half of all emails are opened on mobile devices, according to email marketing statistics. If your emails are not rendering perfectly on smaller screens, you are effectively alienating a large segment of your audience.
Personalization is another truth that consistently boosts engagement. Simply addressing a recipient by their first name is a start, but true personalization goes deeper, segmenting audiences based on behavior, preferences, and demographics. This tailored approach dramatically increases relevance and conversion rates.
Views from the trenches
Best practices
Maintain a healthy list by regularly removing inactive subscribers, which improves your sender reputation and reduces bounce rates.
Prioritize email authentication (SPF, DKIM, DMARC) for all sending domains, as this builds trust with mailbox providers.
Segment your audience extensively and personalize content to increase relevance and engagement.
Monitor your deliverability metrics beyond open rates, focusing on clicks, conversions, and spam complaints via postmaster tools.
Common pitfalls
Believing that purchasing email lists is a quick way to grow, which often leads to poor engagement and blocklisting.
Ignoring mobile optimization, resulting in a poor user experience for a majority of email recipients.
Assuming that plain text emails bypass spam filters or that legal disclaimers can prevent an email from being classified as spam.
Over-reliance on open rates as the sole measure of email campaign success, especially with privacy changes skewing data.
Expert tips
Sender reputation is paramount. Focus on consistent, valuable content and managing recipient feedback channels to maintain a good score.
Engagement is about quality, not just quantity. A smaller, highly engaged list is far more valuable than a large, unengaged one.
Regularly test your email campaigns across various clients and devices to catch rendering or deliverability issues before they impact your audience.
Stay updated on compliance regulations like GDPR and CAN-SPAM, as these laws can have significant implications for your email practices.
Expert view
Expert from Email Geeks says that CAN-SPAM does not require explicit opt-in, only an opt-out mechanism.
2020-10-22 - Email Geeks
Marketer view
Marketer from Email Geeks says that including "FREE!!!" in the subject line can still lead to successful delivery, challenging a common myth.
2020-10-22 - Email Geeks
Embracing the complexities
Email marketing is far from dead. It is a vibrant, evolving channel that demands continuous learning and adaptation. The surprising truths we encounter in this field highlight its complexity and the need for a sophisticated approach.
From understanding the nuances of deliverability to recognizing the true indicators of engagement, embracing these realities is key to unlocking email's full potential. By moving beyond common myths and focusing on data-driven strategies, marketers can build stronger relationships with their audience and achieve remarkable results.
The future of email marketing lies in informed, strategic execution. Continuous monitoring of metrics, adherence to best practices, and a commitment to adapting to new challenges will ensure your email campaigns remain powerful and effective.
