Customers are savvier than they used to be. They know when they've entered a sales funnel. They expect a welcome discount. They're used to the abandoned cart reminder. And they've seen enough promotional emails to recognise the pattern instantly.

That doesn't mean those tactics don't work, they do, but they don't work endlessly. If someone feels like they're hearing from you too often, or the content doesn't feel relevant, they won't always complain. They'll just disengage. Stop opening. Stop clicking. Or quietly unsubscribe. And once that pattern starts, it's hard to reverse.

So the question becomes: how do you keep momentum without accelerating fatigue? One of the simplest and most underused answers is this.

Stop deciding for
your database.

Instead of assuming every subscriber wants every campaign, give them control. Let them choose what actually lands in their inbox:

When can you ask for preferences?

Many businesses think sign-up is the only moment to ask. It's the most popular and often the most effective, but it's far from the only one. Ask at key points across the lifecycle instead: after a first purchase, when someone's been dormant a while, and even mid-campaign, especially if it's been a long time since you last checked in. A simple survey that updates a profile property, or a "manage subscription" page, does the job.

Why it matters

Picture a library, with genres for non-fiction, crime, fantasy, history and fiction. You might love some, ignore others, and even within a genre there are authors or themes that just aren't for you. Your customers are the same, on a smaller scale.

How it improves deliverability

Ask for preferences, and you send less content people don't want, which keeps spam complaints and poor metrics down. The opposite compounds in your favour too: customers who find your emails useful open faster, engage more, click and even share. Klaviyo and inbox providers read those signals as high value, so you land in more inboxes.

More inbox placements mean more potential opens, more clicks, and ultimately more sales.

The most relevant email is the one your customer actually asked for.

Remember that you asked

A big, easy blunder: asking for preferences, then forgetting to actually send segmented emails based on them. Whether you split by group or use show-hide blocks, you must stay true to each customer's choices.