How to Find Wasted Spend Across Performance Max Shopify Products
Performance Max can generate strong sales for a Shopify store, but there is a common problem I see when reviewing eCommerce Google Ads accounts.
Google is spending money on the wrong products.
A handful of products may absorb a large percentage of the budget while other products with better margins, stronger conversion rates or greater commercial importance receive very little exposure.
The overall Performance Max campaign might even show an acceptable ROAS.
But underneath that campaign-level number, some products can be performing extremely well while others quietly burn through the budget.
Quick answer: Why does Performance Max spend money on the wrong Shopify products?
Performance Max decides which products to promote based on the product data, conversion data, bidding objective and signals available to Google.
It does not automatically know which Shopify products are most profitable for your business.
If your campaign is optimising towards sales revenue, for example, Google may favour products that generate conversion value even if those products have poor margins.
Weak product titles, poor product categorisation, incorrect conversion tracking, broad listing groups and putting every product into the same campaign can also cause budget to flow towards products you would not necessarily choose yourself.
The solution is not simply to increase the budget.
You need to understand which products are consuming the budget, which are generating profitable sales and whether your Performance Max structure is giving Google enough useful information to make better decisions.
Performance Max Does Not Know Which Products Matter Most to Your Business
This is one of the biggest misunderstandings about Performance Max.
Google is very good at automation.
But it does not understand your business in the same way you do.
Imagine your Shopify store sells:
Table lamps
Cushions
Throws
Vases
Decorative ornaments
Jewellery boxes
One table lamp might sell for $249 and have a healthy margin.
Another product might sell for $79 with a much smaller margin.
If both products sit inside the same Performance Max campaign and Google is receiving purchase revenue as the conversion value, Google is largely working with the signals it has been given.
It does not automatically understand your supplier costs, freight costs, returns, stock priorities or the products you most want to grow.
That is why I do not like treating Performance Max as a black box and assuming Google will sort everything out automatically.
Automation still needs commercial direction.
How Can You Tell Which Shopify Products Are Using Your Performance Max Budget?
Start by looking below the campaign level.
A Performance Max campaign might show:
$5,000 spend
$15,000 conversion value
300% ROAS
At first glance, that looks reasonable.
But those numbers do not tell you how individual products performed.
You might discover that:
Product A spent $900 and generated $4,500 in sales.
Product B spent $700 and generated $300 in sales.
Product C spent $550 without generating a sale.
Product D barely received any traffic despite having strong margins and good historical conversion rates.
That is a very different picture.
Google Ads now provides broader product reporting for campaigns connected to Merchant Center. From June 2026, Google expanded product reporting so Performance Max product metrics can cover its networks more comprehensively rather than being limited to the older reporting view.
This makes product-level analysis increasingly important.
Do not judge an eCommerce Performance Max campaign purely by the overall ROAS.
Look at what is happening underneath it.
Where to Find Product Performance in Google Ads
In Google Ads, review the Products section for campaigns using your Google Merchant Center product data.
Look at individual products and compare metrics such as spend, clicks, conversions, conversion value and ROAS.
You are looking for patterns rather than one bad day.
Pay particular attention to products that consistently receive meaningful spend without producing enough sales, products receiving a disproportionate share of the campaign budget, products with strong revenue but poor margins, products receiving plenty of traffic but very few conversions, and proven products receiving little exposure.
Google also allows Performance Max products to be organised through listing groups using attributes including item ID, product type, brand and custom labels.
That gives you more control than simply dumping your entire Shopify catalogue into one campaign and hoping for the best.
Should Every Shopify Product Be Included in Performance Max?
No.
I would not automatically advertise every product in a Shopify store simply because the product exists.
Some products are much better Google Ads candidates than others.
A product might have:
Very low margins
Poor stock availability
An uncompetitive price
High shipping costs
A weak product page
Very little search demand
A poor conversion history
Frequent returns
A low average order value
A weak or incomplete product feed
If a product is commercially unattractive, giving Google more budget to promote it is not necessarily going to fix the problem.
Sometimes the right decision is to improve the product data or product page.
Sometimes it is to move the product into a different campaign or product group.
And sometimes it is to stop paying Google to advertise that product.
But Do Not Exclude Products Too Quickly
The opposite mistake is also common.
A Shopify owner sees that a product has spent $40 without a sale and immediately wants it removed.
That can be just as damaging.
A few clicks are not enough evidence to make a sensible decision.
Before excluding a product, look at the wider picture.
How much has it spent?
How many clicks has it received?
How long is your normal buying cycle?
Has it converted previously?
What is the product margin?
Is the product seasonal?
Is stock available?
Is the landing page good?
Is the product price competitive?
Is conversion tracking reliable?
There is no universal spend figure where a product suddenly becomes a bad product.
The decision needs to be based on enough data and on the economics of the individual business.
Your Shopify Product Feed May Be Causing the Problem
Performance Max cannot promote your products intelligently if the product information being sent to Google is poor.
Your Shopify product feed tells Google what you sell.
Google uses information such as your product title, product description, brand, GTIN, product type, Google product category, price, availability and images to understand the product and determine where it may be relevant.
A product called:
Ceramic Lamp
does not provide much context.
A stronger title might be:
White Ceramic Table Lamp with Linen Shade
Now Google has a much clearer understanding of the product.
If one product has detailed, relevant product data and another has a vague title and weak categorisation, they are not giving Google equally useful information.
That can affect visibility and the searches your products are matched with.
This is why I consider product feed optimisation part of Google Ads management for Shopify stores, not a separate technical exercise.
If you have not already read it, see my guide: Is Your Shopify Product Feed Killing Your Google Ads?
Performance Max Can Make a Weak Product Feed More Expensive
A weak feed does not necessarily stop Google from spending money.
That is the problem.
Your products may still receive impressions and clicks.
They may simply be showing for less relevant searches.
You can end up paying Google to learn something your product data should have explained properly in the first place.
This is why increasing a struggling Performance Max campaign from $100 per day to $150 per day can make things worse.
If the underlying product selection, tracking or feed is poor, you have not fixed the problem.
You have simply given it another $50 per day.
Check Your Conversion Tracking Before Blaming Performance Max
Product optimisation depends heavily on reliable conversion data.
If your Shopify purchase tracking is incorrect, Performance Max can optimise towards the wrong signals.
Problems I regularly look for include duplicate purchase conversions, multiple purchase actions set as Primary, incorrect transaction values, add-to-cart actions being treated as primary conversions, missing purchase data and differences between Shopify and Google Ads tracking that nobody has investigated.
If Google thinks a poor product is generating more revenue than it really is, its automated bidding has bad information.
Before making major campaign changes, make sure the purchase data itself can be trusted.
See my guide to Google Ads Conversion Tracking for Shopify for more on this.
Use Listing Groups to Control Which Products Performance Max Can Promote
You are not forced to treat your entire Shopify catalogue as one giant product group.
Performance Max listing groups allow products to be organised using Merchant Center attributes.
Google currently supports attributes including brand, item ID, product type and custom labels for this purpose.
This means you could separate products based on criteria that actually matter to the business.
For example, you might organise products around:
Best sellers: Products with established sales history.
High margin: Products where the economics can support paid acquisition.
Seasonal: Christmas, summer, Mother’s Day or other seasonal ranges.
Clearance: Products that need a different commercial strategy.
New products: Products that need controlled testing.
Low performers: Products requiring closer monitoring before receiving more budget.
The exact structure depends on the size of the store, available data and advertising budget.
More segmentation is not automatically better.
Creating dozens of tiny campaigns can starve Google’s bidding system of useful conversion data.
The goal is sensible control, not complexity for its own sake.
Custom Labels Can Make Shopify Product Management Much Better
Custom labels are one of the more useful tools available to larger Shopify advertisers.
Google Merchant Center supports up to five custom label attributes, which can be used to group products for reporting and campaign management. Google gives examples such as seasonal products, best sellers and clearance stock.
You might use custom labels for:
Margin level
Best sellers
Seasonality
Price range
Product priority
Historical performance
Clearance products
Hero products
This gives you another way to organise the catalogue around your business rather than relying entirely on Google’s standard product categories.
Should You Separate Your Best Products Into Their Own Performance Max Campaign?
Sometimes.
But I would not do it automatically.
If you have a group of proven products generating strong sales and they are being held back by hundreds of weaker products in the same campaign, separating them can make sense.
It can give you better budget control and clearer reporting.
But there is a downside.
Every time you split campaigns, you also split conversion data.
If the store does not generate enough sales, excessive campaign segmentation can make optimisation harder rather than easier.
This is why I look at the actual sales volume, budget, margin, product range and historical performance before deciding how far to split a Performance Max account.
There is no universal Shopify campaign structure that works for every store.
High ROAS Does Not Always Mean Google Is Promoting the Right Products
This is another trap.
Imagine a Performance Max campaign showing a 500% ROAS.
That sounds excellent.
But what if most sales are coming from low-margin products?
Or existing customers?
Or branded searches from people already looking for your store?
Meanwhile, the products you actually want to grow receive very little exposure.
The campaign may be hitting its Google Ads target without achieving the broader commercial goal of the business.
ROAS matters.
But profitable growth matters more.
See Good ROAS for Shopify Stores: What You Should Really Measure for a deeper explanation.
When Should You Exclude a Product From Performance Max?
I normally start considering exclusion when there is enough data to show that a product is consistently consuming advertising budget without producing an acceptable commercial return.
But spend alone is not enough.
I also consider the product’s margin, conversion history, traffic volume, seasonality, stock position, average order value and whether there are obvious feed or website issues that could be fixed first.
For example, I would not necessarily exclude a strong product simply because it has recently stopped converting.
I would first check whether:
The product has gone out of stock.
The price has changed.
Competitors have become cheaper.
The product page has changed.
Shipping has changed.
Merchant Center has an issue.
Conversion tracking has broken.
Search intent has changed.
There may be a fixable reason behind the performance decline.
What I Check When Performance Max Is Spending on the Wrong Products
When I audit a Shopify Performance Max account, I do not start by randomly changing bids and budgets.
I look at the relationship between the campaign, the products and the business.
My review normally covers product-level spend and conversion value, ROAS by product or product group, product margins where available, Merchant Center health, product titles and attributes, product disapprovals, stock availability, listing groups, custom labels, search term quality, conversion tracking, branded versus non-branded traffic, landing pages, bidding strategy and recent account changes.
That normally tells a much clearer story than the campaign-level ROAS alone.
Performance Max vs Standard Shopping
This product-level control issue is also one reason some Shopify businesses should consider whether Performance Max is actually the right campaign type for everything they sell.
Performance Max provides powerful automation and access across Google’s advertising inventory.
Standard Shopping provides a different level of visibility and control.
Neither is automatically better.
The right choice depends on what you are selling, how much conversion data you have, your advertising budget and how much control you need.
Read Performance Max vs Standard Shopping for Shopify: Which Is Better? if you are deciding between the two.
The Real Problem Usually Is Not Performance Max Itself
It is easy to blame Performance Max.
Sometimes that criticism is justified.
But usually the deeper problem is the setup around it.
Poor product data.
Weak tracking.
Too many products competing for a limited budget.
No consideration of margins.
Products grouped badly.
Low-quality search traffic.
No regular product-level analysis.
A Performance Max campaign cannot fix those problems by itself.
Giving Google better inputs and stronger commercial boundaries usually matters more than endlessly changing the target ROAS.
What Should Shopify Stores Do Next?
If Performance Max is producing sales but you are not sure which products are actually responsible for the result, start there.
Do not immediately rebuild the campaign.
Do not double the budget.
And do not exclude twenty products because they had a bad week.
First identify which products are receiving the money.
Then identify which products are producing sales.
Then compare those results against margins, stock, business priorities and product quality.
Once you understand that, decisions about exclusions, listing groups, custom labels, campaign structure and budgets become much easier.
That is how Performance Max should be managed.
Not as a black box.
As an advertising system that still needs commercial oversight.
Frequently Asked Questions
Why is Performance Max spending more money on some Shopify products?
Performance Max uses Google’s automated bidding systems to decide where it believes advertising spend can achieve the campaign’s conversion objective. Products with stronger signals, conversion history or predicted performance may receive more exposure. That does not necessarily mean they are the most profitable products for your business.
How do I see which products Performance Max is spending money on?
Use product reporting within Google Ads and review individual products or product groups rather than relying only on the campaign total. Compare spend, clicks, conversions, conversion value and ROAS to identify where your budget is actually going.
Should every Shopify product be included in Performance Max?
No. Products should be assessed based on factors such as margin, stock, demand, conversion history, pricing and strategic importance. Automatically advertising every product in your Shopify catalogue can spread a limited budget across products that are unlikely to generate a worthwhile return.
Should I exclude Shopify products that are not converting?
Not immediately. Make sure the product has received enough meaningful traffic before judging it. Also check product feed quality, pricing, stock, landing page quality, seasonality and conversion tracking before deciding the product itself is the problem.
Can a bad Shopify product feed waste Performance Max budget?
Yes. Weak product titles, missing attributes, poor categorisation and incorrect product information can make it harder for Google to understand what you sell and match products with appropriate searches. Better product data can improve the quality of the information Performance Max has available.
Can I control which products Performance Max advertises?
Yes. Performance Max listing groups can include or exclude products using Merchant Center attributes such as item ID, brand, product type and custom labels. This allows you to manage groups of products rather than automatically advertising your complete catalogue.
What are custom labels in Google Merchant Center?
Custom labels are internal product attributes that can be used to organise products for advertising and reporting. You can use them for groups such as best sellers, seasonal products, margin ranges, clearance products or other categories relevant to your business. Google Merchant Center supports five custom label fields.
Should I put my best-selling products in a separate Performance Max campaign?
Sometimes. Separating proven products can give you more control over budget and reporting, but too many campaigns can fragment your conversion data. The decision should be based on the store’s sales volume, budget, product range and the amount of data available.
Does a high Performance Max ROAS mean the campaign is working well?
Not necessarily. ROAS measures advertising revenue against advertising spend, but it does not automatically account for product margins, returns, customer quality or other business costs. You should review product-level performance and profitability as well as the overall campaign ROAS.
Can product feed optimisation improve Performance Max?
Yes. Product information from Google Merchant Center helps Google understand the products being advertised. Improving titles, product types, categories, identifiers, images and other product data can give Google better information to work with when matching products with potential customers.
Is Performance Max better than Standard Shopping for Shopify?
Neither campaign type is automatically better. Performance Max provides greater automation and access across Google’s advertising inventory, while Standard Shopping can provide a different level of control. The right choice depends on the store, budget, conversion data and advertising objectives.
Need Help Finding Where Your Performance Max Budget Is Going?
If your Shopify store is spending money through Performance Max but you are not confident the right products are receiving the budget, I can review the account properly.
I look at the Google Ads campaigns, individual product performance, Google Merchant Center, Shopify product feed, conversion tracking, search traffic and campaign structure to identify where money is being wasted and what I would fix first.
I personally audit and manage every account.
There are no junior account managers or offshore handovers.
Request a Google Ads audit and I’ll take a look at what is happening inside your Performance Max campaigns.
Phil Adair is a Sydney-based Google Ads consultant with more than 17 years of hands-on experience. He specialises in Shopify and eCommerce advertising, including Performance Max, Google Shopping, Merchant Centre and product feeds, and also manages selected lead-generation campaigns for service and B2B businesses.
Phil works directly on every account, with no junior account managers or offshore handovers. His focus is practical: reduce wasted ad spend, fix tracking and product feed problems, and improve profitable sales.
Learn more about Phil Adair or request a free Google Ads audit.