What Actually Happens When You Click Send? Understanding Email Deliverability Issues

Let’s look at what actually happens when you click “send” on an email campaign, because it’s a complex series of steps, involving various technologies and protocols designed to deliver your message to recipients’ inboxes. The journey of your email campaign is more complex than you think. And if you understand it, then you can diagnose and fix email deliverability issues more easily. 

Here’s a simplified overview of what happens:

1. Sending the Email

Dispatch: The campaign is dispatched from the email marketing platform (ESP) you’re using. During this process, your emails can be sent from either a dedicated or shared sending domain and infrastructure. A dedicated sending domain and IP address mean that your campaigns are sent using a domain and IP unique to your organization, enhancing your control over sender reputation. On the other hand, a shared domain and IP involve your emails being dispatched alongside other businesses’ emails, which can be more cost-effective but may impact deliverability if others on the platform are engaging in poor emailing practices. 

→ One thing to examine with deliverability issues is whether you can send from a dedicated sending domain, and the overall reputation of your ESP. For example, Klaviyo doesn’t allow any users to import cold lists, so its reputation tends to be higher than average – one of the reasons they’re considered Best In Class. 

2. Processing by Recipient Servers

Authentication: As your email is sent, it undergoes authentication checks by recipient email servers (i.e. Google, Outlook, Yahoo) to verify that it’s from a legitimate source. This involves analyzing the sending address domain and checking for specific DNS records like SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting, and Conformance). 

→ It’s a best practice if you’re serious about email to set up these records on your domain. This is a one-time project involving your web developer or email partner with access to your domain. Making changes takes up to 7 days to start to see improvements. 

Spam Filters: Incoming emails are analyzed by the recipient’s email server using spam filters. These filters scrutinize the email’s content, headers, sender reputation, and other factors to determine if the email should go to the inbox, a spam/junk folder, or another categorization like promotions. Spam filters also consult blacklists. So if you’re on any blacklists, you’re automatically going to see your message either bounce or go to spam. 

→ Avoid the use of trigger words like “SEX!” and “FREE CASH” and writing in all caps. Also look at the tool you’re using and make sure your header elements are compliant, you’re not using too many images, and overall the content of your emails isn’t “spammy.”

→ There are also “invisible” triggers like issues with your email’s header. A mail service like Klaviyo and Hubspot will automatically incorporate best practices in the email headers, but not all do so it’s worth ruling out these issues. Testing with a tool like Litmus can help you identify these technical triggers.

3. Delivery to the Recipient’s Inbox

If the email passes the spam filters, it’s delivered to the recipient’s inbox. However, there are some issues on the recipient’s inbox that may prevent a message from coming through – including if their mailbox is full (soft bounce). 

Bounces: If an email can’t be delivered (due to a non-existent email address, a full mailbox, or server issues), it’s reported as a “bounce.” Bounces are classified into “soft” (temporary issues) and “hard” (permanent failures, such as an invalid email address). High bounce rates can harm your sender reputation.

→ This is why it’s important to look at bounces closely. 

4. Engagement With the Email

Opens and Clicks: Engagement with your email, such as opens and clicks on links, is tracked (if enabled) and reported back to your ESP. This engagement is crucial for assessing the effectiveness of your campaign and can influence future deliverability. 

→ The more positive engagement you have, the more ESPs will recognize your message as good. This is the reason why it’s better to send emails to engaged lists. Especially high volumes. Also checking that your email tracking is set up properly is important for this step. 

Unsubscribes: Recipients may choose to unsubscribe from your mailing list using the link provided in your email. It’s essential to process these requests promptly to comply with laws like CAN-SPAM and to maintain list hygiene.

→ Unsubscribes happen. As long as your marketing ESP is processing these appropriately, then this shouldn’t have an impact on your deliverability. We recommend our clients to have the “opt out of all lists” enabled unless there’s some very specific use cases. 

Marks as Spam: When a recipient marks your email as spam, it not only removes the email from their inbox but also signals to the email service provider that your content wasn’t wanted. Too many spam complaints can severely impact your sender reputation and deliverability.

→ Marking as spam is the worst for deliverability and a guarantee that your sender reputation will suffer if you go above industry standards. How to not get marked as spam? Don’t send spam. Don’t send to people who don’t want to hear from you. Don’t send too often (learn to let go), and respect unsubscribes.

Understand That It’s a Feedback Loop

Your sender reputation, a score assigned by ISPs and email providers, is influenced by factors like bounce rates, spam complaints, unsubscribe rates, and engagement. A good reputation helps in achieving better inbox placement. The more you send to smaller, engaged lists, the more you’ll be respected as a strong sender, and the better your email deliverability will be. 

Adaptation by Spam Filters: Repeated negative indicators (high bounces, spam marks) can lead email providers to adjust their spam filters to be more likely to block or filter your future emails.

The more you have negative indicators, the less your emails will get through, the worse your sender reputation, and the worse your email deliverability. 

Less Is More

After you click “send” on an email campaign, your message passes through a number of technical checks and there are steps at each point you can take to improve deliverability. 

However, the fact that this whole system operates as a feedback loop is critical to a strong email marketing strategy. It’s why “less is more” when it comes to getting results from email, and if you’re working on your email marketing strategy you’ll take this into account. 

Things like keeping your list clean, having a mechanism to identify and let go of subscribers who are no longer engaging with your content, is important. Things like not cold emailing, not importing lists. 

This doesn’t mean you can never email a fuller list. It just means you have to do it cautiously and make sure you don’t overdo it. As an example of this, we regularly send to 3- and 6-month engaged lists. And then anywhere from once a month to once a quarter, we’ll send to 12- or 24-month engaged lists. We regularly look at the campaign, look at the data, and create segments for campaigns where we see there’s a chance to “fold in” those who might be interested in the topic even if they haven’t engaged recently. 

As an email marketing agency, our livelihood depends on a strong understanding of email deliverability. If emails aren’t reaching inboxes, no one is getting results. 

When To Seek Help

Deliverability issues are complex and we genuinely wish those problems on no one. It’s a hole you have to climb out of. The good news? It is possible. And with some strategic support, you can not only recover your email metrics but also ensure you don’t have deliverability issues again. 

However, it isn’t always easy or straightforward. Here’s when to reach out to an expert for support: 

• You’re having trouble diagnosing the problem.
• You need the problem resolved as quickly as possible. 
• You need support with email best practices like list cleaning, opt-in management, or consent management. 
• You need alternatives to purchased lists. 
• You need the ability to measure and monitor email deliverability to spot issues early on.

About Centric Squared

Centric Squared is a growing email marketing agency driving significant revenue for our clients through Email and SMS Marketing. With a focus on CRM-driven marketing, our team of global marketing experts has generated $3 million in revenue for our clients last year alone. We’re committed to transforming businesses with data-driven strategies that enhance customer engagement and foster resilient growth. 

Our Email Deliverability Consulting Services are designed to diagnose, troubleshoot, and resolve these issues, putting your email marketing back on the path to success. Schedule a consultation today.