I like to think of my role as a retention marketer as the person responsible for everything that happens after the customer gets to the site. So the ad worked-yay! The customer clicked the ad, and now they’re here. This is when they enter my court.

Now, how do I get them to sign up for email and SMS? How many sign up? Of those who do, how many actually make a purchase? How quickly do they make that first purchase? And then, how many of them come back for a second purchase? How soon does that happen?

When I go to ecommerce events, all I hear is Meta, Meta, Meta. And when I subscribe to brands’ email lists, I’m often bombarded with far too many emails-and far too little relevance. But why?

My name is Michal Liberman. I’m a 2025 Klaviyo Champion and the CRM director at the handbag company The Sak. In this article, I share practical strategies and proven tactics you can implement to improve retention, measure success, and become an indispensable driver of long-term revenue.

Understanding the value of customer retention

Why retention matters

On a good day, our customer acquisition cost is $40. THAT’S ABSURD! But what’s even more shocking is the idea that after spending $40 to get a customer’s email address, so many brands drive them away with poor CRM practices. And what’s the actual cost of having a customer come back again? Just a few dollars per year.

To put it in perspective:

• About 10% of my new prospect traffic subscribes to email and SMS.
• Roughly 15% of those new subscribers make a purchase through email or SMS within the first 7 days.
• Then, about 30% of customers who make one purchase come back for a second purchase within 6 months!

Imagine having to spend $40 on each of those customers all over again. That’s why retention programs matter.

My favorite metrics to track when I evaluate the efficiency of my CRM program

• Average time between sign-up and first purchase: Set a goal to make that time shorter. You might discover that more than 50% of your customers purchase on the same day they sign up-in which case you can focus on optimizing your very first welcome message. (There’s never too much A/B testing here.)
• Percent of customers returning from first to second purchase: Set a goal to bring more customers into a second purchase. How do you do that? Personalization at scale, the right person with the right message at the right time, and well-planned automated flows.
• Average time between first and second purchase: Aim to shorten that window, too. The big drop often happens between the second and third purchase, so try to catch the customer while they are still excited about your brand.
• Revenue per send: The higher your revenue per send, the more efficient your program. In my experience, your flows should be generating at least $0.70 per send if you’ve set them up correctly. Your campaigns should generate at least $0.50 if you’re taking segmentation seriously (more on this later).
• Percent of revenue from automated flows vs. marketing campaigns: Make it your mission to close the gap. You should and can create an evergreen email trigger for any scenario that will deploy at the right time.
• Churn rate: This is the percentage of customers who stop buying. Your goal should be to make this rate smaller and smaller every year.

Impact on growth

According to research from Bain & Company, improving retention by even 5% means you can spend less on paid ads and see profit increases of 25% or more.

Core CRM strategies for improving retention

Sign-up pop-up optimization

Let’s say your ad manager spent $40 per customer to bring them to your site. That means you better get their email address!

Optimize your pop-ups by testing variations: quiz, social proof, long vs. short text, different offers, etc. Do you know which incentive drives the most conversions? Free shipping, discounts, exclusive content? Test everything. Spoiler alert: your spin-to-win version might be the one that gets the most addresses…

Loyalty program optimization

My retention rate for customers who are part of my loyalty program and are earning/redeeming points regularly is 40% higher than customers who do not sign up for loyalty.

Your loyalty program needs to be exciting and genuinely rewarding, especially if your brand is like The Sak and has a presence on Amazon, at Nordstrom, etc. It should also tie to your reviews and user-generated content so that it feels like a genuine community.

Let customers work toward that higher tier while earning free gifts, perks, and early access to drops and sales. The goal is to make customers feel recognized and valued.

Behavioral triggers and personalization at scale

We’re in the business of sending the right message to the right person at the right time. That starts with setting up baseline flows:

• Welcome series
• Browse, cart, and check-out abandonment
• Post-purchase

Then, you can take it a step further. Here are a few of the less common triggers I like to use:

• All loyalty triggers (you earned points, your points are expiring, you are X points away from the next tier)
• Birthday triggers
• Unique collection abandonment campaigns that tell the story of the collection
• Up- and cross-sell campaigns within and between categories
• Post-first-purchase (re-educate your customer and tell them more about their select product)
• Risk of churn and reactivated

Always use A/B testing to optimize content and timing.

Tips for building more triggered flows (instead of relying on marketing sends)

• Make your best full-price emails evergreen by using dynamic product catalogs and behavioral data. At The Sak, our color stories are the best full-price emails. So, we created an evergreen email for each color, showcasing all the styles in that color. Using dynamic product catalogs, we were able to organize all of the styles according to colors. I trigger color stories as a browse abandonment follow-up after 14 days (“Is yellow your favorite color?”)
   
• Use Klaviyo’s RFM (recency, frequency, monetary) analysis to identify segments and trigger automations. The point in time for when customers enter each RFM stage is the perfect time to hit them with the right message. For example, “joined a segment = RFM At Risk” is your time to send them an offer that progressively gets more aggressive. Once your customers lapse, it’s a lot harder to bring them back.

Tips for successful segmentation

• Set up Klaviyo’s free preference center and use it to 1) let customers opt down instead of opting out, and 2) let them tell you what they are most interested in and how often they would like to be communicated with. Then, you can segment based on that zero-party data. This is a fantastic way to allow customers to tell you exactly what they want so you can tailor their experience accordingly.
• Use your RFM stages as segments to exclude inactive customers from marketing messages. Yes, you can-and should-exclude inactive customers from your daily and weekly sends. Unless it’s a big sale, don’t bother. Including your inactive customers will tank your performance metrics.

So… what does a CRM manager actually do? We own everything that happens AFTER the customer comes to the site and extends the traffic into a lasting relationship. It might start with a pop up, but it will lead to email, sms, direct mail, app, loyalty rewards programs, reviews and referral. Our job is to make sure we don’t just acquire the customer but we also keep it.

And check out the articles in this series: 

Yours truly,

Michal Liberman