Spend is going out. Orders aren't coming in. Somebody is about to suggest pausing the account.
Search "Google Ads not converting" and you'll find a dozen posts offering ten reasons why: weak ad copy, poor keyword intent, slow landing pages, wrong match types, bad audience targeting. Every item on those lists is a real thing that can happen.
The trouble is that a list of ten possible causes is not a diagnosis. Worked through in the wrong order, you can spend three weeks rewriting ad copy for an account whose conversion tag stopped firing in April.
So this is a triage order rather than a list. Five questions, and you stop at the first one that gives you a bad answer, because everything after it depends on the answer being good. For a Shopify D2C brand, the first two catch the large majority of cases.
First: are your Google Ads not converting, or can you just not see the conversions?
Before diagnosing a performance problem, rule out a measurement problem. These look identical in the interface and have nothing else in common.
Pull Google Ads conversions for a closed 30-day window and compare against Shopify orders for the same dates. If Shopify shows healthy order volume and Google Ads shows very few conversions, your ads are converting fine and the tracking isn't reporting it.
That distinction matters beyond reporting. Smart Bidding optimises toward the conversions it can see. An account with broken tracking doesn't just misreport, it actively degrades, because the algorithm is being trained on a fraction of the real signal. Every day it runs that way, it gets worse at finding buyers.
Common causes on Shopify: a theme update that removed a tracking snippet, an app migration that left the Google & YouTube channel disconnected, consent-mode settings suppressing conversion pings, or a checkout extensibility change that broke a thank-you-page tag. None of these announce themselves.
If those two numbers disagree, stop here. Nothing below this line is diagnosable until they don't.
Second: is the account optimising toward the wrong thing?
The second most common case isn't broken tracking. It's tracking that works perfectly and measures the wrong event.
Open your conversion actions and look at which are set to Primary. If add-to-cart, begin-checkout, or a page view sits alongside purchase as a primary action, the account is being told those are all successes. Smart Bidding will duly go and find people who add to cart and leave, because that's what you asked for.
This is the failure that looks most like "Google Ads doesn't work for us." Conversions are high, the ROAS column looks respectable, and the bank account disagrees with both.
The fix is unglamorous: one primary purchase action, everything else demoted to secondary for observation only. Expect reported conversions to fall sharply and reported ROAS to change shape. That is the number becoming true, not performance dropping.
An Australian jewellery brand arrived with exactly this, plus duplicate purchase trackers on top. Once it was cut to a single primary action and the account restructured by product and region, it produced A$331,092 in tracked revenue at 3.0x blended ROAS against a 1.3x break-even. Nothing about the traffic changed. The account simply started aiming at the right thing.
Third: is it converting, just not profitably?
Sometimes the ads convert perfectly well and the complaint is really about margin.
"Not converting" and "not making money" are different problems with different fixes, and they get conflated constantly. If you're generating orders at a 2.5x ROAS and your break-even is 3.3x, the campaign works and the economics don't. Rewriting ad copy will not close that gap.
Work out your break-even ROAS from contribution margin, after cost of goods, fulfilment, transaction fees, and returns. Most brands calculate on gross margin alone and land around 30% too optimistic. You can run yours in about two minutes, and we covered why the simple formula overstates it in detail.
If the answer is that you're above break-even but below target, that's a scaling and structure conversation, not a troubleshooting one.
Fourth: is the traffic wrong, or is the landing experience wrong?
Only now is it worth looking at what most checklists start with.
Pull the search terms report, not the keyword report. It shows what people actually typed. On ecommerce accounts the usual finding is spend against research-intent queries — "best", "review", "how to", competitor names, or broad category terms that were never going to buy today.
If search terms look right and they still don't buy, the problem has left Google Ads and moved onto your site. Check the obvious things in this order: does the product page load quickly on mobile, is the price competitive against what's showing next to you in Shopping, is stock actually available, and does checkout work on a phone. A slow or broken mobile checkout is the single most expensive site problem an ad account can inherit.
For Shopping and Performance Max specifically, the mismatch is often in the feed rather than the page. If product titles are templated across variants, Google matches your products to queries they were never right for, and the traffic arrives poorly qualified through no fault of the campaign. You can score your feed against 40 checks free to rule that in or out.
Fifth: does the campaign have enough data to learn from?
Target ROAS and Maximise Conversions both need conversion volume to work with. On a small budget with a high-value product, an account can go days between conversions, and the bidding strategy is effectively guessing.
Two symptoms point here. Spend that fluctuates wildly day to day, and a budget that doesn't fully deploy despite plenty of available impression share.
If you're in that position, a simpler bidding strategy usually outperforms a smart one. Manual or Maximise Clicks with tight targeting will beat Target ROAS on an account that can't feed it. Revisit once conversion volume supports it.
Related: if ads aren't showing at all rather than showing and failing, check Merchant Center for product disapprovals before assuming a bidding problem. Disapproved products don't serve, and the campaign will report low impressions rather than an error.
The Google Ads not converting triage order, in short
- Reconcile conversions against Shopify orders. Rules out a measurement problem masquerading as a performance problem.
- Check which conversion actions are Primary. One purchase action. Soft conversions demoted.
- Compare ROAS against your break-even. "Not converting" and "not profitable" need opposite fixes.
- Read the search terms report, then the landing experience. Research intent and broken mobile checkout, in that order.
- Check conversion volume against bidding strategy. Smart bidding on thin data is guessing.
Work down that list and stop at the first bad answer. Most accounts where Google Ads are not converting fail at step one or two. The rest is rarely the problem.
What not to do while you're diagnosing
Don't pause the account. It's the instinctive move and it destroys the conversion history the bidding algorithm needs, adding a fresh learning period on top of whatever was already wrong.
Don't change several things at once. Fix tracking, wait, read the data. Then change structure. Simultaneous changes mean you learn nothing about which one worked.
Don't scale spend to "give it a chance". If the account is aimed at the wrong thing, more budget buys more of the wrong thing, faster.
The takeaways
- Rule out measurement before performance. Google Ads conversions versus Shopify orders, same window. This one check resolves most cases.
- Soft conversions marked Primary are the most common silent cause. The account is converting; it's converting toward browsing.
- Broken tracking degrades the account, it doesn't just misreport it. Smart Bidding trains on what it can see.
- "Not converting" and "not profitable" are different problems. Check against break-even before troubleshooting anything.
- Diagnose in order and change one thing at a time. Don't pause, don't scale, don't rewrite ads first.
If your Google Ads aren't converting and the first two checks come back clean, the problem is usually structural rather than technical, and that needs the whole account looked at rather than a symptom chased. Our eight-point PPC audit covers that sequence, or we'll run it on your account free and you keep the findings either way.