Email on Tap, Episode 7: Seth Charles, Principal Email Deliverability and Industry Relations Manager, Iterable

Anthony Chiulli, 250ok’s director of product marketing, delivers yet another interview with a powerhouse of email knowledge: Seth Charles, principal email deliverability and industry relations manager at Iterable, a growth marketing platform.

Iterable and 250ok share a common love of email and a strong belief in its power to drive stronger customer engagement. Anthony and Seth got together to chat about some of the things they think about as industry influencers, including metrics marketers should care about (but perhaps don’t) and so much more.

Marketers, this is one you won’t want to miss.

Total Run Time: 10 minutes
00:23 – Overview of Iterable, and Seth’s role in deliverability
00:37 – Difference between deliverability and delivery rates
1:12 – Important metrics beyond an ESP’s that marketers should pay attention to
2:42 – Difference between domain-based reputation versus IP-based reputation for marketers
3:45 – Why the “warming period” now includes new IP addresses and email domains
4:40 – What makes deliverability at Gmail so challenging
5:45 – How Gmail Annotations may change the dialogue for senders fighting over primary tab placement
6:59 – Irritating email marketing ‘pet-peeves’ Seth sees from marketers
8:08 – How poor email address acquisition and validation tactics can impact email performance downstream.

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Anthony Chiulli
Hi, everyone, and welcome back to another exciting episode of Email on Tap, I’m your host, Anthony Chiulli. And today, I’m joined by Seth Charles, the principal email deliverability and industry relations manager at Iterable. Seth, thanks so much for coming on the program.

Seth Charles
Yeah, I appreciate it, thank you.

So tell me a little bit about Iterable and your role there.

Yeah, so Iterable is basically a growth marketing platform that allows senders to communicate with their customers in a bunch of cross-channel ways. So whether it be SMS, or email, or push notifications.

And oftentimes we talk about deliverability, which you’re clearly an expert in, one of the most common questions that I typically see, is what’s the difference between delivery rates and deliverability rates? Can you explain that?

Yes, so it’s super common. So typically, when we talk about delivery rates, that’s a technical handshake, a successful transmission of a message, right? So we’re asking a receiving server to accept a message, and they say, yes, we’ll accept it. The deliverability rate is a little bit harder to gauge. And that’s whether or not your message is actually delivering to an inbox or not.

And talking about deliverability, most often than not, marketers and brands are focusing on what I like to call metrics from their ESP, or ESP-centric metrics. Those would be open rates, delivery rates that you just talked about and defined, spam complaints, unsubscribes and opens and clicks. But there’s metrics and signals beyond what an ESP can typically offer that mailbox providers or ISPs are also paying attention to. What are some of those metrics, and why should marketers care about them?

Yeah, well there’s actually a ton, right, so like after a message gets received by a server, say Gmail or whatever, a lot of things go into whether or not the message goes to inbox. And the things that inboxes or the receiving servers weigh are things like whether or not a message was starred, or whether a message was originally delivered to spam and then actually moved by the recipient to the inbox, or whether it was replied to or forwarded. So those are all a ton of kind of behind-the-scenes metrics that a sender should definitely be concerned with.

So it’s almost as if the ISPs are looking at their own set of signals beyond what an ESP has visibility into that’s happening in their webmail or in their inbox experience, that are certainly important to reputation.

Yeah, traditional metrics are always going to be super important to worry about. But that’s just really the tip of the iceberg on kind of what goes into filtering decisions that they make. So it’s always important to understand kind of how your users are going to interact with that mail over time.

And speaking of reputation, there’s been this evolution as of late from more of an IP-based reputation for senders that are tied or anchored to an IP address, and more of an evolution and shift into what we call domain reputation. Can you talk a little bit about domain reputation and why it’s important?

Sure, so yeah, to your point, IP reputation is always going to be around, it’s always going to be a thing. But as we’re finding that in the IPv4 space, so the four octets of an IP, as we start to run out of room, there’s been a shift towards this kind of IPv6, which is another octet added onto the end. So it’s going to be virtually impossible to track and maintain reputation at scale for that many IPs. So for that reason, there’s been a huge shift over the last three, four years and something I expect to continue. Where the reputation that lives behind the authentication protocols, so like the SPF records, and the DKIM records, and the sending domain. There’s going to be a huge shift towards that, because it’s all a bit harder to spoof at scale, and a little bit easier to track as a sender and as a recipient.

So does that mean now, when we talk about warming, which is a common practice for any sender, either obtaining new IPs or moving to a new ESP, that the warm-up process now extends beyond just IP warming? And now, if you have a new domain, or you spin up a new domain, the new domain needs to be warmed as well?

Yeah, definitely, so if you’re warming, obviously, if you’re moving ESPs, or you’re transitioning to a new IP, those are things that senders are pretty well-versed in, that you have to warm up. But also, any time you’re adding a subdomain, or you’re essentially shifting any of the sending elements, meaning your SPF domain, or your DKIM domain, or your “from” domain, or your IP. Anytime you’re changing one of those fundamental elements of a message, you’re going to want to at least kind of reel in the volume a little bit, to at least do it in a real deliberate way. And that way you don’t raise any red flags there.

So let’s shift gears and talk about Gmail, the largest webmail provider on the planet, right? What I’ve typically seen is when marketers of brands have challenges with deliverability, oftentimes it’s with Gmail. What makes Gmail so difficult and so unique to deliver to?

Well, they’re challenging because they are the biggest, and because they are the most cryptic about a lot of the metrics, kind of the feedback that they give to senders, and also because they’re the most sophisticated. So I think that it’s fairly well known now that Gmail is a recipient by recipient type filter. So their machine learning is so advanced and they have thousands of different elements that go into their filtering decisions. So it makes it really hard for senders to kind of get a grip on how to change programmatically. Because again, Gmail is so unique to each recipient to where you really have to tailor your sending practices to deliver as much value to the individual recipient as you can.

Yeah, I certainly have experienced that, and oftentimes what I see with Gmail, and Google in itself. is leading from the front in innovation regarding their webmail design, features, filters, machine learning. And most recently, the Gmail annotations, which has been exciting in this space. Talking about Gmail annotations, do you think that Gmail annotations for the Promo tab will change? Or maybe optimistically stop the conversation for marketers demanding of how to get their mail out of the Promo tab and into the Primary tab? Do you think that will change that dialogue?

It’ll change it for sure, so I don’t know that it’ll necessarily stop it. Because senders typically want the Primary tab, because it, as a general rule, will generate a little bit stronger engagement. But it’ll definitely change it, so it’s providing a little bit more incentive for senders to be a little bit more strategic about the way that they’re marketing. So whether it be your featured images, or some kind of featured CTA or something within the message that you want to highlight in the annotation. So it’ll make it a little bit more dynamic and exciting for senders. But yeah, I think it’ll definitely be something to keep an eye on, and something that senders should be excited about.

Yeah, I would agree. You’ve worked extensively over your career on the frontlines in deliverability consulting with many brands. What are some of your pet peeves of marketing or email marketing that you’re seeing customers do, that just irritate you or get under your skin?

Yeah, one is definitely going to be when senders don’t really pay that close attention to engagement when they are modeling their campaign frequency. So if they’re sending 30 messages to somebody in a month that opens every single message, but they’re also sending 30 emails a month to somebody that hasn’t opened a message at all from them in six months. I mean that’s going to be a huge red flag and something that’s definitely going to damage reputation. So senders that don’t really pay attention to engagement is definitely a problem. And then also, just kind of anecdotally, we deal a lot with senders that don’t really want to take agency or ownership over deliverability. And honestly, it comes back to that the senders are the ones that are driving the reputation. It’s not necessarily the pipe to kind of the email universe, it’s more so it’s on them, so they can own it.

Yeah, I think a really good point to harp on, is marketers and senders own their reputation. And it’s not the sole responsibility of the ESP or the platform that you sit on, it’s an excellent point. To close this off, I want to talk about data for a minute and data fuels digital transformation. And it’s kind of the center stone for many digital marketing strategies for brands. But what often goes unnoticed is the quality of data. And from a deliverability perspective, I’d be curious to ask your opinion on kind of that top-of-funnel approach of getting clean and verified and validated email addresses onto your list at first. Because if you don’t, what are the ramifications downstream that you’ve seen with deliverability when brands are perhaps doing co-reg, or not verifying email addresses or purchasing list? Or just have kind of loose-goose acquisition sources for email addresses?

Yeah, well I mean top-of-funnel is everything, right? So you’re only going to be as healthy at scale as you are kind of in the way that you collect data in the first place. So for senders that are purchasing lists, that’s a great way to get on a significant blacklist. That’s a great way for the major providers like Microsoft, and Gmail, and Verizon now. I mean, you basically spotlight yourself as somebody that’s not going to be doing things in an ethical way. And then we talk about things like spam trap hits, and all these things that kind of feed into your overall deliverability. So for senders that don’t really pay that close attention to top-of-funnel hygiene, there’s a great chance that they’re going to run into problems.

Well said. Seth, this has been very insightful, thanks so much for sitting down with me. And thanks everyone for tuning in, we hope to see you for another episode of Email on Tap.

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