Outside of new customer acquisition, reactivating customers can be the most frustrating and expensive exercise you ever take on, also providing some of the worst performance metrics you'll ever see. While there's been hundreds of articles written on the topic, here's my slightly different take that hopefully will expand how you think about this.

With Google's recent launch of its Inbox email client (still invite-only at this writing), everyone is rushing to declare what this means for subscribers and marketers. Excuse me if I yawn. Who knows whether Inbox will get more traction than other client configurations trying to change how we use email? Sure, you need to know how new email client iterations affect performance. But it's not the whole story. The inbox itself, how subscribers use it and the impact it has, is changing. It's no longer just the device, app or client that defines the inbox. You must also understand the …

Reputation matters more than ever. That's the clearest takeaway from our most recent research into sender reputation and inbox placement. Looking at the entire mailstream segmented by IP reputation shows that messages from the top-ranked senders reach the inbox, while everyone else struggles or outright fails. Compared to past years, the reputation bar is far, far higher now.

It seems as if the marketing world has a new slogan. Once upon a time it was "email is dead," but most have come around to believe that email definitely has a place within the marketing construct. But the new slogan seems to indicate that email marketers are a dying breed -- at least when it comes to a marketing organization's need for them. Instead of damning the channel, marketers are now rallying against the specialists that build and execute email programs themselves.

Pop quiz, marketers! How do you feel about the new Inbox by Gmail? A) Annoyed. This is probably worse than Gmail tabs. B) Intrigued. What a fascinating opportunity. C) Confused. What's Inbox? If you answered B, you're in the right line of work.

The paid-owned-earned media model has become dated. Social media, SMS/MMS, and email marketing have been awkwardly forced into the owned media slot, where they don't really belong. It's time to expand the model and acknowledge the uniqueness of these newer channels as well as our far from absolute control over them.

I believe the reason more budget isn't allocated to email is that industry members struggle to sell it effectively to their organizations. Have you ever been sold a car? Dealerships use a four-square selling method. They help you find the car and establish a Sales Price. They negotiate your Trade-In (if applicable). They discuss Cash Down and Payment. And finally, they discuss the Monthly Payment. To sell email's value, you need a strategy. Here's the four-square approach for email marketers.

Google has done it again. Inbox, the newest iteration of Gmail (still in invite-only stage at this writing), promises to revolutionize the inbox (again) and has email marketers worrying about how to respond (again). And, here I am (again), asking email marketers not to get sidetracked by day-to-day distractions like Gmail Inbox, Priority Inbox, Unroll.me, symbols in subject lines and the best time or day to send email. Yes, they might affect inbox or email activity at some point. It's important to understand how the inbox has been evolving since email became a major conversion channel in the 1990s. But …

What makes an email successful? Delivering the right message to the right person at the right time on the right device. As a communicator, I like to think of these attributes as context. Here are some ways to get the context right and improve your program.

Ready or not, here it comes. A wave of marketing that has been growing for years -- contextual marketing -- will reach new heights in 2015. If your organization does not have the ability to capture and leverage a significant amount of data for personalizing and "right-timing" your customer communications -- including data relevant to the current state of the customer (location, device, environment, past behaviors, etc.) -- you risk fatiguing your customers with non-relevant messaging and falling behind competitors who are doing it right.