In our favorite session from this month's Email Insider Summit, marketers shared what they learned from some excruciating email faux pas. Zillow's Jamie Plankenhorn shared her nightmare when a little-seen mistake involving negative UGC feedback slipped into an email campaign. Then Reddit happened.

How can machine learning really transform your approach to email marketing? Square's Anna Bowles told the Email Insider Summit how ML can predict the best time of day to send an email for every individual customer. By using these predictive models that learn from user behavior, the company is realizing enormous efficiencies and turning waste into more effective and new email inventory.

While everyone else is throwing video, audio, and animation into the new multimedia in-box, custom footwear startup Shoes of Prey impressed the Email Insider Summit this month with her retro tactic. Text. Yes, plain text, when used sparingly, can bring a new (or old) authenticity to certain messages, said their Chloe Dutschke.

Email does not live in a vacuum. As Director of Email Julie Witsken explained at the Email Insider Summit earlier this month, all messages have to be understood as part of a multi-channel experience the consumer has with the brand. The organization laid out principles, a North Star, all aspects of the company had to reflect.

The "390-degree" view of the customer should be considered more of a North Star than a benchmark, says Total Wine & More's Bart Thornberg. Don't get distracted by the bits of data you don't really need to know. You can start with just two or three points and see big returns.

When outdoor gear retailer Cabela's asks their customers what they want, the brand listens...and follows. The basic brand proposition for the company - "It's in your nature." The brand identity came directly from focus groups the retailer held with customers.