The Gist

• Email isn’t failing — attribution is. Performance drops often stem from SMS, push and paid media cannibalizing conversions and muddying credit, not true email decline.
• Omnichannel without orchestration backfires. Without coordinated messaging and shared metrics, brands create redundancy, fatigue and zero-sum channel competition instead of incremental value.
• Most issues are operational, not creative. Over-frequency, poor deliverability, weak automation and flawed design quietly erode results more than campaign quality.
• Automation is the biggest missed lever. Top programs drive ~25%+ of revenue from triggered emails, yet many teams overinvest in batch sends instead of optimizing lifecycle flows.
• Email health still matters. Low engagement signals deliverability risk, creating a downward spiral that suppresses visibility and performance.
• The real fix is unified measurement. Shifting from channel metrics to customer lifetime value exposes true growth and prevents internal competition across teams.

While no one has claimed email marketing is dying for many, many years, some marketers have become increasingly concerned with performance declines, despite the channel generating returns on investment that are often at least twice as high as most other channels.

If your organization is concerned about your email marketing performance, here are some of the root causes I’ve been seeing that go beyond the usual economic or competitive pressures.

Table of Contents

• Activity in Other Marketing Channels
• Advertising Activity
• A Lack of Channel Integration
• Poor Email Channel Health
• Overly High Email Frequencies
• Email Design Issues
• Inadequate Automated Campaigns
• Your Email Problem Might Not Be Your Emails

Activity in Other Marketing Channels

Email marketing doesn’t operate in a vacuum. It’s affected by all the other channels your brand operates, including SMS and push marketing.

As brands have ramped up those two channels in recent years, we’ve seen them undermine email marketing. Not only are some email signup forms replaced by SMS signups, which dampens email list growth, but the brand’s email marketing campaigns are used to nudge subscribers to sign up for SMS and to download their mobile app, creating an opportunity for push opt-ins.

Of course, nudging customers to opt into additional channels is smart. I’ve found that customers who have opted into two or three of the major marketing channels (email, SMS, and push) are anywhere from two to nine times more engaged and valuable than single-channel subscribers. That’s a huge opportunity.

However, if your messages across channels aren’t thoughtfully differentiated and orchestrated to minimize redundancies, then you’re just cannibalizing email for the sake of the other channels, instead of generating additional value.

It’s also worth noting that while the email channel is expected to support the growth of SMS and push, that expectation is rarely reciprocated. It’s nearly impossible to find examples of brands using their SMS and push programs to nudge those subscribers to sign up for email.

Advertising Activity

Just as other channels can cannibalize email marketing, advertising can, too. For instance, I’ve seen marketers alarmed by a sudden downshift in email performance who then discover that their advertising team used their email list to power targeted digital ads. It’s not that this can’t be effective, but in many ways they paid money to generate some conversions they would have captured with their owned media in time.

It also clouds attribution by making the ad team look like superstars. But it’s only because they’ve targeted consumers who are highly qualified thanks to the nurturing the email marketing program has done. At the same time, the cannibalization puts budgetary pressure on the email team, essentially penalizing them for successful nurturing.

A Lack of Channel Integration

Sometimes the advertising, SMS and push teams are aware that they’re simply shifting conversion attribution from one part of the ledger to their part of the ledger, and do it because they’re rewarded for doing it. Sometimes, they’re unaware.

Regardless, it’s a failure of the brand to adopt a true omnichannel marketing approach that focuses on increasing customer-centric metrics such as customer lifetime value rather than channel-specific metrics, which allow gamesmanship across channels.

As brands grow additional channels beyond email, it becomes increasingly vital to unify and orchestrate as many marketing channels as possible from a single, highly integrated platform. Along with deploying a customer data platform, adopting a best-of-suite approach to your martech stack allows tighter orchestration, more cohesive messaging and performance visibility that reveals true growth and exposes zero-sum attribution shifting.

With those big non-email-related issues out of the way, let’s turn to problems we often see in email programs themselves.

Poor Email Channel Health

Marketers should primarily focus on bottom-of-the-funnel metrics instead of surface metrics like opens and clicks. However, if your conversion rates and email revenue numbers are flagging, it’s wise to look at your open and click rates. If your open rates (stripping out auto-opens from Apple) are under 10%, that may be a sign of deliverability problems or impending issues.

That’s because engagement is a major component of spam filtering algorithms. So, low engagement can lead to your emails being blocked or routed to the spam folder, which reduces your engagement further.

Overly High Email Frequencies

Related to poor channel health, there’s the issue of email frequency. Since I first joined the email marketing industry in 2006, email frequency has increased by roughly 10% … every year. In some ways, email marketing is a victim of its own success. It’s so effective that brands just send more and more of it, which drives down per email performance.

The new wrinkle is that most B2C brands appear to be at the level where they’re on the backside of the frequency optimization curve. They’re now seeing significantly diminishing returns from sending an incremental email, especially when you factor in list churn and fatigue.

I’ve seen numerous cases where brands were able to reduce their overall email volume and increase email revenue. They accomplished this by reducing email frequency to less engaged subscribers while simultaneously sending their most engaged subscribers highly targeted campaigns using personalization, segmentation and automation.

Email Design Issues

A shocking percentage of brands are sending emails that don’t adapt well to dark mode, don’t score well on accessibility tests and are challenging to read and engage with on mobile devices.

That last one is particularly shocking, considering that mobile-optimization has been a priority for well over a decade and that most B2C emails are now read on mobile devices. While many brands use responsive email design, which allows their email to adapt to the user’s screen size, that’s not enough to be mobile-friendly. The biggest opportunity is for brands to use more reasonable font sizes. I recommend 16pt as a baseline for body copy, with heads and subheads being larger.