• by Loren McDonald , Op-Ed Contributor, August 13, 2009

Ask any of my fellow Email Insider columnists (or other industry pundits) what is the No.1 key to email marketing success. I bet they'll reply with some variation of "relevance." But what does "relevance" mean? What makes one email more relevant than another?

Now, ask the average email marketer to define "relevance." Answers might range from "Sending the email my subscribers signed up for" to "Whatever I think my subscribers want to read" and even "If it they opted in, then it's relevant."

So I was curious and posed the question on Twitter of what "relevance" means. Here are a few responses (not surprisingly, mostly from email industry folks):

 "Relevance in email, to me, means I get what I want (whether or not I know what that is), when I want, how I want it."

"The higher my affinity for the brand, the more 'gap' I am willing to tolerate. ... Affinity is an influencing factor on relevance."

"When the gap is short or nil between the content and what is top of mind in my life."

"Timing and message (content)."

"Relevant email marketing delivers the right message at the right time. Timing + Interest = Relevance."

"Relevance = an email that I can personally relate/identify with and panders to my customer profile ."

Most agreed that a core principle of relevance is "the right message at the right time." With that in mind, here is my attempt at defining what goes into "the right message" and "the right time."

The Right Time:

Wanted. While there are exceptions, the foundation of relevant email is usually that a subscriber has knowingly and actively opted in to receive your emails.

Trusted and Recognized. Subscribers might have given you permission, but unless they trust your brand and email content going forward, they will bail. They must know at a glance that the email is from your company, division or specific message stream. Your sender ("from") name, subject lines and value of previous emails aid recognition.

Expected. Your subscribers check their inboxes specifically to see if your email has arrived. A regular sending schedule helps reinforce this expectation.

Delivered. Perhaps it's obvious, but if your emails don't reach the inbox or frequently wind up in your subscriber's junk folder, they're toast.

Timely. Your email cadence must fit what subscribers expect and what is appropriate for the content. The timing must match current trends, buying patterns, news events and other factors consistent with your value proposition. Your emails must "know" (through profiles, segmentation, behavior, etc.) when a subscriber wants to book a trip to Hawaii or replace an old PC with a new netbook.

Surprising. Surprising in a good way, like when the counterperson at your local coffee shop yells out your name when you walk in. Your emails must delight subscribers with special content, discoveries, recommendations, reminders or even rewards, just like Cracker Jack once delighted us with a different toy in every box.

The Right Message

Usable. Do you make it easy for subscribers to do what THEY want to do, whether it's to get more information on a product or change their email addresses? Are your emails designed to render well on multiple devices, in the preview pane and with images blocked?

Personalized. The email reflects the subscriber's preferences (content, format, frequency, interests), purchase history and other details. Dynamic content, segmentation, Web analytics integration and trigger-based emails drive personalization.

Differentiated. The inbox has never been more crowded. Like a product on a supermarket shelf, your emails must be strongly positioned and differentiated from your competitors. They must break through to that "inner circle" of emails.

Valued. Your emails must provide clear value, whether strong content or great deals. They inform, notify and remind. They solve problems, from dispensing gardening tips to suggesting the perfect 25th-anniversary gift for one's spouse.

Humanized. An underappreciated component of relevance is personality and humanism. People don't want to read email from faceless corporations. The more "human" your emails are, the more your subscribers will anticipate and interact with them.

Did I miss something obvious, or do you think I'm off my rocker? What else constitutes email relevance? I welcome your comments below.

Until next time, take it up a notch!