4 email marketing mistakes that quietly kill your conversions

Sometimes, it’s the smallest things in your email setup that have the biggest impact.

Tiny details that seem harmless can quietly chip away at your conversions and leave you wondering why your emails feel a little… meh.

Whether you’re just getting started with Klaviyo or you’ve been using it for a while without seeing results, these four common email marketing mistakes might be why your emails aren’t converting the way they should.

Here are four things I wouldn’t recommend doing in your email marketing (and what to do instead).

1. Keeping double opt-in turned on

Hot take: just turn it off. Thank me later.

Unless you’re in a specific industry that legally requires it, double opt-in isn’t essential—even under GDPR.

The problem? It breaks the flow. A customer signs up expecting a discount or welcome email… but instead they get a generic “confirm your subscription” message (which half of them ignore). That’s a conversion killer.

What to do instead:
✔️ Turn off double opt-in unless you're dealing with spam issues
✔️ If you do need it on, brand the confirmation email with your logo, tone of voice, and a clear CTA
✔️ Make the experience feel intentional, not robotic

Looking for Klaviyo help for your Shopify store? Fixing this one tiny setting can make a big difference to your list growth and welcome email conversion rate.

2. Asking for too much info in your pop-up

If your sign-up form is asking for everything except a customer’s blood type… it’s too much.

At the sign-up stage, you want to reduce friction. Asking for a first name? Fine. Asking for preferences, birthdays, phone numbers and a checkbox to agree to the privacy policy? That’s how you lose a subscriber before they even join.

What to do instead:

✔️ Keep it simple. One field = better conversions.

✔️ Ask for just an email address. You can gather more info later using Klaviyo’s profile enrichment tools.

✔️ Add a strong hook, think why should they sign up?

Need support with pop-up strategy for Shopify? A well-designed form with a clear value offer can 2x your sign-up rate overnight. That’s the kind of thing we fix inside The Email Fix.

3. Using WELCOME10 as your discount code

I get it, it’s easy to remember. But here’s the problem:

• It kills urgency (nobody believes WELCOME10 is going to expire).

• It doesn’t feel personal.

• Customers will reuse it again and again on repeat purchases.

What to do instead:

✔️ Use Klaviyo’s dynamic discount codes to personalise offers

✔️ Add urgency with expiry timers in your flows

✔️ Make it feel tailored: “Here’s 10% off just for you, [first name]” > “WELCOME10”

This small shift alone can drive a big bump in conversions and average order value. It's one of the most common tweaks I recommend in my Klaviyo audits for ecommerce brands.

4. Forgetting a CTA at the top

Subscribers shouldn’t have to scroll a mile before they see a button.

If your email opens with a big block of text and no action, you’re missing the point (and the sale). You need to make it as easy as possible for them to say yes.

What to do instead:

✔️ Place a clear CTA above the fold

✔️ Add a hyperlinked header or button within the first few lines

✔️ Repeat the CTA further down so there’s always an easy “click here” available

Want to learn how to improve email conversions on Shopify? Start by putting your best offer where your reader can see it straight away.

So, why does this matter?

If you’re guilty of one of these mistakes, don’t panic; it’s not a disaster.

But if you’re doing a few of them at once? That’s probably why your Klaviyo emails aren’t pulling their weight.

I work with product-based businesses every day who are doing everything else right—great website, loyal customers, steady traffic—but their email marketing feels flat. More often than not, it’s these small (fixable!) details that cause the problems.

Whether you need help building flows from scratch or just want a professional pair of eyes on what you’ve already set up, getting a second opinion can seriously transform your results.

Get your email fix

That’s exactly what we do in The Email Fix, our done-for-you Klaviyo audit for Shopify brands.

You’ll get:
✔️ A full review of your flows, campaigns + sign-up forms
✔️ A mapped-out customer journey strategy (20 flow emails)
✔️ Email wireframes, ready to build
✔️ A plug-and-play template to refresh your email design instantly

It’s practical. It’s personalised. And it’s built to help your emails start doing the heavy lifting (so you don’t have to).

👉 Book your Email Fix audit now

Email doesn’t have to be overwhelming. But it does need a plan. Let’s sort yours.