If you've got limited time and money (and who doesn't), the big question is - do you push harder on acquisition, or fix the site so more visitors actually buy?
Most people guess. Or they do whichever feels easier. That can be expensive.
The truth is, there's a right answer and it's different for every business. It depends on where you are now, what your numbers look like and where the biggest bottleneck is. This post gives you a simple framework to decide, using a few sanity metrics and some straight maths. No guesswork. No "let's try both and see what happens."
There are two main ways to increase sales through your website:
Lever 1: Get more traffic
SEO, Google Ads, Paid Social, PR, partnerships — anything that brings more people to your site.
Lever 2: Convert more of the traffic you've got
CRO (Conversion Rate Optimisation), UX improvements, landing page tweaks, checkout flow fixes — anything that turns more visitors into customers.
Both levers work. But most businesses pick the wrong one first.
Why?
Because traffic feels like growth. It's visible. You can see the numbers go up. It's exciting.
Conversion rate optimisation feels like housekeeping. It's less glamorous. And it's harder to sell internally because it doesn't come with a big shiny traffic spike.
But the reality is; if your site leaks, more traffic just means more leaks.
If 98% of your visitors leave without buying, sending more traffic to the same broken experience is just burning money. You're paying to show more people a site that doesn't work.
On the other hand, if your conversion rate is solid but you're only getting 500 visitors a month, optimising the site further won't move the needle. You need more people through the door.
So how do you know which lever to pull first?
Here's a simple decision framework. Work through these questions in order, and you'll know where to focus.
This is the most important number.
Conversion rate = (number of conversions ÷ number of visitors) × 100
For eCommerce, a conversion is usually a purchase. For lead gen, it's usually a form submission or phone call.
So, what’s your benchmarks?
If your conversion rate is below benchmark, you've got a conversion problem. Fix that first. Scaling traffic when your conversion rate is 0.5% is like pouring water into a bucket with a hole in it. You'll spend a fortune and wonder why nothing's working.
If your conversion rate is at or above benchmark, you might have a traffic problem. For example, you're converting 3% of visitors and you're still not hitting revenue targets. The issue probably isn't the site, it's volume. You need more people through the door.
If you're getting less than 1,000 visitors a month, you need more traffic and better conversion. But start with quick CRO wins first, because scaling traffic is expensive. And if your site doesn't convert, you'll burn through budget fast.
Fix the obvious things like landing page friction, mobile UX, trust signals, then start scaling traffic.
If you're getting 5,000+ visitors a month with low conversion, then CRO is your biggest opportunity. You've already got the traffic. You just need to convert more of it. Even a small improvement in conversion rate will have a massive impact on revenue. If you're getting 10,000 visitors a month at 1% conversion (100 sales), improving to 2% doubles your sales without spending a penny more on acquisition.
If you're getting 5,000+ visitors a month with solid conversion, traffic is the play. You've optimised the site. Now you need more volume.
This is where the maths gets important.
CAC = how much you spend to acquire one customer
LTV = how much that customer is worth over their lifetime
If your CAC is too high relative to LTV, scaling traffic will kill you.
Here’s an example. You're spending £50 to acquire a customer who spends £60 once and never comes back. Your margin is £10. That's not sustainable.
In this case, you need to fix conversion and retention before you scale. Otherwise, you're just losing money faster.
If your CAC is healthy and you've got margin to scale, traffic is the play. For example, you're spending £20 to acquire a customer who spends £100 and comes back twice a year. Your LTV is £300+. You've got room to scale.
In this case, the bottleneck isn't efficiency, it's volume, so it’s best to look at spending more on acquisition.
Look at your analytics. Where are you losing people? If they're bouncing on landing pages then conversion is a problem. Your messaging isn't clear, your offer isn't compelling, or your page is slow/broken.
If they're adding to cart but not buying is another conversion problem. Something's wrong with your checkout flow. Maybe there’s too many steps, unexpected costs, lack of trust signals, poor mobile experience.
If they're browsing multiple pages but not taking action, again, that’s a conversion problem. They're interested, but something's stopping them from converting. Could be unclear CTAs, lack of urgency, or friction in the journey.
If they're not finding you at all, this one’s simple! Your traffic is the problem. You need better visibility, so look at what marketing channels will offer your business the best tye of visibility. Is it SEO, Paid Ads, or both?
Once you've worked through the framework, you'll know which lever to pull. Here's what to focus on for each.
You should focus on CRO if:
Quick CRO wins to focus on:
Is your headline clear? Does it match the ad or link that brought people there? Is the CTA obvious? Can people understand what you're offering in 5 seconds?
How many steps does it take to buy? Are you asking for too much information? Are there unexpected costs (shipping, fees) that only appear at the end? Is guest checkout available?
Do you have reviews, testimonials, trust badges, guarantees? Are they visible on key pages? Do people know you're legitimate?
Is your site easy to use on mobile? Are buttons big enough to tap? Is text readable without zooming? Does the page load quickly?
Slow sites kill conversion. If your site takes more than 3 seconds to load, you're losing people before they even see your offer.
Do people understand what you're selling and why they should buy from you? Or is your site full of jargon, vague claims, and corporate waffle?
Even small improvements here can have a massive impact. Going from 1% to 2% conversion doubles your revenue without spending more on traffic.
You should focus on traffic if:
Quick traffic wins to focus on:
Target people who are actively searching for what you sell. High intent = higher conversion rate. Start with a small budget, test, and scale what works.
Retarget people who've visited your site but didn't buy. Use lookalike audiences to find new people who match your best customers. Facebook, Instagram, TikTok — pick the platform where your audience actually is.
Fix technical issues, optimise existing pages, target long-tail keywords with clear intent. SEO takes time, but it's one of the most cost-effective ways to scale traffic long-term.
Get featured on relevant blogs, podcasts, or industry sites. Build relationships with complementary brands. This won't give you instant results, but it builds authority and drives qualified traffic over time.
If you've got an existing customer base, use it. Email campaigns, referral incentives, and loyalty programmes can drive repeat traffic and sales without acquisition costs.
The key is to start small, test what works, and scale the channels that give you the best return.
This isn't "CRO vs traffic forever". It's "which one first?"
Once you've fixed the biggest bottleneck, you move to the next one.
The cycle looks like this:
The best businesses cycle between the two. They don't pick one and ignore the other. They focus on whichever lever will give them the biggest return right now, then move to the next one.
If you're just starting out, the order usually goes:
If you're further along, you're constantly testing and iterating on both. But you're still prioritising based on where the biggest opportunity is.
Here's the short version:
Focus on CRO if:
Focus on traffic if:
Focus on both (but start with CRO) if:
Don't guess. Look at the numbers. Work through the framework. Then focus on the lever that'll give you the biggest return.
Most businesses waste money because they're pulling the wrong lever. They scale traffic when their site doesn't convert. Or they obsess over tiny CRO tweaks when the real problem is that no one's finding them.
The quickest route to more sales isn't the same for everyone. It depends on your conversion rate, your traffic volume, your CAC, and where people are dropping off.
Work through the framework. Look at the numbers. Then focus on the bottleneck that's costing you the most revenue right now. Once you've fixed that, move to the next one. That's how you grow without wasting money.
