Email marketing has evolved far beyond newsletters and promotional blasts. Today, success depends on a careful balance of technical precision, audience psychology, and long term relationship building. With mailbox providers using increasingly sophisticated filtering systems and subscribers becoming more selective about what they engage with, brands can no longer rely on outdated tactics or surface level metrics.
Deliverability is shaped by user behavior as much as authentication settings. Growth is influenced by the quality of subscribers, not just the size of a list. And the most effective campaigns are designed to build trust and momentum over time rather than chase short term spikes in clicks.
At Website Planet, we set out to explore what is actually working right now in email marketing. We asked industry experts to share the overlooked factors affecting inbox placement, the metrics more brands should prioritize, and the strategies that make large scale campaigns feel genuinely personal.
Their insights reveal a clear theme: mastering email marketing today requires both technical discipline and human connection.
What is the most overlooked factor that has the biggest impact on email inbox placement today?
The most overlooked factor is behavioral filtering. Teams often obsess over technical configuration like SPF, DKIM, and DMARC, but inbox placement today is driven far more by how recipients consistently interact with your emails. Low engagement patterns, deleted without read events, or a lack of replies signal to mailbox providers that users don’t find your messages valuable. Even with flawless infrastructure, these negative signals gradually push a sender into spam.
This is especially true in B2B cold outreach, where you are emailing people who do not know you yet. In this context, email warming becomes critical because it builds a history of positive, human-like interactions around your sending identity before you start scaling. Tools like MailReach focus specifically on creating those positive behavioral patterns in a B2B environment, which helps establish the trust signals mailbox providers expect.
Improving your behavioral signals through warming, relevance, segmentation, and reply-worthy content will always have more impact than adding another technical record.
Damien Brenelière, Co-Founder & CEO at MailReach
How do you technically implement and monitor inbox placement to ensure emails consistently land in the primary inbox rather than promotions or spam folders?
There’s no magic bullet for inbox placement: ISPs like Google, Yahoo, and Microsoft keep their filtering algorithms opaque. To maximize deliverability, start by ensuring recipients genuinely want your emails: use double opt-in and captchas to block bots, and avoid using deceptive signup tactics. Next, make sure DMARC and DKIM are set up correctly: this is an absolute necessity in 2026. Finally, when sending large amounts of emails, slowly ramp up sending volume to avoid rate-limiting by ISPs. Once you have these measures in place, you can consider using third-party monitoring services to discover if there are still issues with specific ISPs.
Phillip, Founder of Keila
What is the most overlooked metric in email marketing that more brands should track?
The Most Overlooked Metric: Subscriber Lifetime Value (SLTV)
While most brands fixate on immediate campaign metrics like Open Rates or Click-Through Rates, the most overlooked metric is Subscriber Lifetime Value (SLTV).
At Wave Evolution, we believe that an email address is more than a data point for a one-off sale; it is a long-term asset. SLTV measures the total revenue generated by a subscriber from the moment they join your list until they unsubscribe or become inactive.
Why it matters:
- Shifts Perspective: Instead of chasing “vanity” spikes, brands focus on long-term engagement and retention strategies.
- Informs Acquisition: If you know your SLTV is high, you can justify a higher Cost Per Lead (CPL) to acquire quality subscribers.
- Identifies “Churn Risk”: By tracking how value diminishes over time, you can trigger automated re-engagement flows before a subscriber is lost.
Tracking SLTV forces a brand to move away from “blasting” and toward sophisticated segmentation. When you optimize for the lifetime of the relationship rather than the next 24 hours, you build a sustainable, high-ROI ecosystem that transcends temporary algorithm shifts.
Ethan Tan, Senior Digital Strategist at WaveEvolution
How do you ensure your emails stay out of spam folders?
To keep emails out of spam folders, a number of tactics must be employed. First, ensure your DNS records are very clean and you have appropriate records set up for DMARC and DKIM to help provide instructions for what to do if authentication fails. (Sound techy geeky? It is!) Second, those records need instructions to create automated email reports that are sent to (usually) a special email address that collects these failure reports. Someone must actually examine them to determine why authentication is failing. (Oh, my!) And that someone must fix the errors. Complicated? You bet!
You can reduce the amount of email that lands in spam folders with some non-techy steps: Use double-opt in rules for folks to join your email lists. Use services, such as ReCaptcha and Cloudflare, to verify you have real people subscribing to your lists. (You can do this at list sign up.) Don’t forget to scrub your lists regularly: Ask recipients to opt-in periodically to ensure contacts are genuine and that you’re not simply sending to dead letter boxes.
Most importantly, make your content utterly fascinating to generate engagement and feedback. You can add simple polls to emails so recipients can vote up or down on quality.
Marcia Macomber, Creator-in-Chief at Cornucopia Creations
How do you craft email campaigns that feel personal even with large audiences?
I believe email campaigns feel personal when they’re created around building what I call the “Know, Like, and Trust Factor”.
When I work with clients, this is exactly what we focus on inside each email sequence. They start with alignment. We make sure every email matches what someone actually signed up for. If a subscriber opted in for help with fitness, business, or systems, that’s what shows up in their inbox. When messaging feels aligned, people stay engaged because it feels honest, not salesy.
I help clients write emails that sound like them: human, conversational, and clear, rather than stiff marketing copy. That often means weaving in stories, real-life examples, and lessons learned, not just information.
We also prioritize providing value. I help my clients to include actionable tips, frameworks, or small steps readers can implement immediately to get a “free win” on their own. Those quick wins build credibility and confidence long before a paid offer is ever introduced.
By the time an offer is presented, it feels like a natural next step, not a pitch because the relationship has already been built. That’s how email marketing scales while still feeling deeply personal.
Jenn Lamb, Owner of Create & Automate with Jenn
