With 11 million subscribers and 2,000 new products launching every day, One Kings Lane’s email marketing efforts are not only front and center in its marketing strategy, but also getting constant attention and iterations.

One Kings Lane sends its customers one to two emails per day. “They open them; they look for them,” said One Kings Lane director of product management Barron Ernst, during a conversation with CommandIQ co-founder and chief executive Noah Jessop and Susa Ventures’ Eva Ho at our GrowthBeat conference earlier this month.

Disclosure: CommandIQ is a GrowthBeat sponsor.

That’s an unusually high number of emails. Most companies would be happy to have their customers open one two emails per week, let alone daily.

Through its constant testing and analysis, One Kings Lane has been figuring out what works and what doesn’t work in its emails. For example, beautiful photography really resonates with its visually driven users, so the company is continuing to optimize its emails with high-quality photographs.

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One Kings Lane has been using CommandIQ, a tool for testing and tracking customers’ behavior and interactions with messages and communications, and has been customizing its emails to different segments of customers and their behaviors.

“Barron’s team is constantly iteratively testing … It’s about giving the customer a better experience,” said Jessop.

But it’s not about testing just anything. A lot of elements and tweaks don’t really have any meaning and won’t get you any closer to your goals. “Testing button color and placement is not necessarily the right thing to do,” said Ernst.

Moreover, this testing process won’t mean anything unless key metrics are set from the start and throughout. The data won’t mean anything without context and metrics guiding its analysis, which both Jessop and Ernst agreed on.