What You’re Doing Wrong in Your Marketing Emails [According to an Email Expert]

If you’re still following outdated email marketing rules, you might be hurting your results more than helping.

Email continues to be one of the most powerful tools in a marketer’s toolbox—but it only works if you know how to use it right. Even experienced pros make subtle but damaging email marketing mistakes that limit performance, reduce engagement, and drop messages straight into the junk folder.

We took a fresh look at some of the most talked-about advice from email marketing expert Jay Schwedelson—founder of SubjectLine.com and host of Try This, Not That! For Marketers Only!—to uncover what most brands are still getting wrong.

Whether you’re running small campaigns or scaling major email initiatives, here are three straight-shooting lessons that will help you course-correct, modernize your tactics, and understand how to improve email open rates in a meaningful way.

Stop Doing This in Your Emails: Lessons from a Pro

Lesson 1: Get the Dang Thing Opened.

You can have the most compelling copy in the world—but if no one opens your email, it doesn’t matter.

Jay is quick to point out that while everyone focuses on message content, most marketers ignore the elements that matter before the click: subject lines, preheaders, and send timing.

“So many people obsess over what’s inside the email, but on average, less than 50% of people even open it,” he says.

That 50% mark is generous—email marketing best practices 2025 show that average open rates hover closer to 42%. Want better than average? Your subject line strategy matters.

So, what’s the fix?

Focus on first impressions. Your email subject line tips should include action words, personalization, curiosity, and yes—even emojis when appropriate. Don’t treat the subject line and preheader like afterthoughts. They deserve just as much strategy and testing as your core content.

If your open rate improves, your chances to boost email engagement skyrocket. It’s the entry point to every other conversion.

Lesson 2: Throw Out Your Banned Words List.

For years, marketers have avoided words like “free,” “winner,” or “urgent,” assuming they trigger spam filters. Jay calls this one of the most persistent email marketing mistakes still in circulation.

“That’s old information,” he explains. “These rules were relevant 10 years ago, but not anymore.”

Today’s spam filters don’t work the way they used to. It’s not specific words that cause problems—it’s lack of engagement. The key to avoid spam filters in email marketing is simple: send emails people actually want to open and click.

That means you don’t have to censor your creativity or be afraid of exclamation points, capital letters, or excitement. If the word “free” gets attention and drives clicks, use it. If a subject line with energy gets results, lean into it.

Remember: the more your recipients interact with your emails, the more trusted your domain becomes. Those very words you feared might just help boost email engagement and keep you in the inbox where you belong.

Lesson 3: Don’t Worry About What “Everyone Else” Is Doing.

There’s a tendency in marketing to chase originality to the point of self-sabotage. Jay pokes fun at how brands try so hard to stand out that they avoid anything they think feels “overdone”—like holiday emojis or common phrases.

But here’s the truth: consumers don’t compare your email to 25 others in real-time. They look at yours in a split second and decide whether to open. If a shamrock emoji on St. Patrick’s Day improves open rates, does it matter if a few other brands used one too?

“Just because you think everybody’s doing it doesn’t mean you shouldn’t,” Jay reminds us.

The solution? Test everything—especially the tactics you’re tempted to dismiss. Sometimes, the strategies you resist are the ones that deliver the biggest lift.

Instead of shying away from trends, embrace the ones that perform. This mindset shift is essential if you’re serious about applying email marketing best practices in 2025 and beyond.

Use data, not ego, to guide your creative decisions. Whether you’re choosing an emoji, a subject line format, or a special offer, test it—and keep what works.

Conclusion

Email isn’t dead. Far from it. But what is fading fast are outdated habits and assumptions that no longer serve your audience—or your goals.

Want to know how to improve email open rates and avoid spam filters in email marketing? It’s not just about clever copy or elegant design. It’s about relevance, engagement, and testing what actually works.

So take a hard look at your next send. Are your subject lines compelling? Are you afraid of certain words that could actually help? Are you overthinking originality instead of optimizing performance?

Let go of the myths. Revisit your strategy. And use these proven insights from an email marketing expert to fix the quiet mistakes that are holding you back.

Because at the end of the day, mastering email marketing best practices in 2025 is less about following rules—and more about challenging them.