If you’ve been following along, you’ll know we’ve already covered how to get your Google Search campaigns back in shape. But Shopping and Performance Max (PMAX) campaigns are a different beast—and they need their own attention.
These campaigns are driven by automation, machine learning, and product data. But if you assume they’re “set and forget,” chances are you’re wasting budget, missing opportunities, or both.
This blog takes you through five key areas that often go unchecked but can have a major impact on Shopping and PMAX performance. They’re not silver bullets—but if you haven’t looked at them recently, now’s a good time.
Let’s get into it.
1. Is Your Product Feed Doing Its Job?
Your feed is the foundation of any Shopping or PMAX campaign. And if it’s not clean, complete, and well-optimised, you’ll struggle no matter how much you spend.
Check your product titles—are they clear and keyword-rich? Do they reflect how people actually search? Have you filled out all available attributes like GTIN, brand, MPN, availability, and condition?
Google relies on this information to decide when and where to show your products. And if key fields are missing or messy, you’re limiting your visibility and wasting impressions.
It’s also worth reviewing your Merchant Center account for warnings and disapprovals. A single product issue can quietly block an entire category from appearing.
A solid product feed sets the stage, but how your campaigns are structured, and how your budget is split, matters just as much. Let’s move on.
2. Are You Controlling Budget and Priority?
In Shopping and PMAX, Google chooses how and where to spend your money. But you still have levers—if you use them correctly.
If you’re running both Standard Shopping and PMAX together, you need to be aware of how they interact. PMAX usually overrides Shopping unless you carefully control campaign priorities and segment budgets.
In Standard Shopping, campaign priority settings (low, medium, high) allow you to influence which campaign gets preference when more than one could serve. In PMAX, you’ll want to make sure budget isn’t being hoarded by one asset group or goal.
If your ROAS or CPA suddenly changes, it could be a signal that your budget is drifting toward less profitable areas.
So now we’ve got feed and budget basics under control, but to really understand what your campaigns are doing, you need to get a look behind the curtain. Or in this case, the search terms.
3. Can You See What’s Triggering Your Ads?
Search term visibility is limited in PMAX and restricted in Shopping—but it’s not gone entirely.
Use the Insights tab in Google Ads to uncover top search themes, and pair it with GA4 or Search Console data to identify intent patterns. In Standard Shopping, the Search Terms report still exists—and it’s essential for spotting irrelevant queries.
You can (and should) still use negative keywords on Standard Shopping, and account-level negatives can sometimes influence PMAX. It’s not perfect, but it’s better than letting Google run entirely unchecked.
If your clicks feel high but conversion quality is low, it’s worth investigating what’s being matched to your products.
Search terms tell you what’s working at the top, but the ads themselves need to carry that relevance through. That’s where asset groups come into play.
4. Are Your PMAX Asset Groups Actually Relevant?
Too many PMAX campaigns rely on one generic asset group. That’s a problem. Asset groups are the closest thing you have to ad groups in PMAX, and they control which messages, creatives, and product sets are shown to different audiences.
If you’re bundling dozens of products together with generic messaging, don’t be surprised when results feel all over the place.
Structure your asset groups by intent or product category. That way, your creative stays aligned with the user’s journey—and you give Google’s machine learning something solid to work with.
We’re nearly there, but before wrapping up, there’s one final check that can completely skew your results if it’s off: your tracking.
5. Is Your Conversion Tracking Giving You the Full Picture?
PMAX optimises for conversions. But if those conversions aren’t being tracked accurately, or if they’re misaligned with your business goals, you’ll be scaling the wrong results.
Review which actions are being counted. Are you tracking sales, form fills, phone calls—or just page views? Are you using data-driven attribution, or is everything lumped into last click?
Also check your attribution window. A 30-day default might work for some industries—but if your product cycle is shorter or longer, you’ll need to adjust it.
Bad tracking equals bad optimisation. Period.
Wrapping Up
Shopping and PMAX campaigns can be powerful—but only when managed with care. If you’re not regularly reviewing feed quality, budget allocation, asset structure, and tracking, you’re flying blind.
These five checks are a good starting point. If they’ve surfaced a few things to look into, great—start there.
Next up, we’ll be moving into another channel. But if you want to talk more about your PMAX or Shopping setup, I’m happy to help.
Chris Chapman, Director at Finsbury Media
linkedin.com/in/chris-chapman