How to Audit PMax and Make Automation Work for You
Stop accepting "automation" as an excuse for wasted spend. Here is how to see exactly where your money is going and how to fix it.
PMax Strategy: Quick-Scan FAQ
-
Only if you let it be. PMax is opaque, not invisible. The problem isn't the automation itself, but the lack of commitment to its audit and architecture.
We can’t control the bidding algorithm directly, but we have full control over the inputs (feeds, assets, exclusions) and the reporting scripts used to visualize outputs. Strategic control lives in the inputs and how we structure our accounts.
-
No, UNLESS they are running it because it is easy and “hands off”.
Otherwise, No. PMax is an efficient tool for scaling volume and revenue.
However, it is a poor tool for margin protection and accurate attribution without expert stewardship and decisions. The issue isn't using PMax; it's the acceptance of its default, wasteful settings. A strategist ensures PMax serves your P&L, not just Google’s volume goals.
-
At least weekly for high-volume, high-AOV accounts. The frequency of change in the placements and search terms PMax chooses requires constant vigilance. The time spent on one weekly forensic audit (checking video spend, app placements, and URL expansion) will deliver a higher return than two weeks of non-strategic busywork.
It has been several years since Google introduced Performance Max (PMax), forcing a shift from granular control to algorithmic automation. By now, most agencies have accepted the narrative: “It’s a black box. Just feed it creative and conversion data, and let it run.”
I reject that premise.
While PMax is a powerful tool for scaling e-commerce revenue, but obviously "setting and forgetting" is a recipe for inefficiency.
In 2025, the question isn't "What is Performance Max?" The question is: "How much of my PMax budget is being wasted on low-quality inventory that claims credit for sales it didn't generate?"
If rising costs are your bigger concern, see my piece on cost‑intent strategy for smarter spend.
If you are managing a high-volume e-commerce account, you cannot afford to fly blind. Here is how to crack open the black box and audit your PMax campaigns for actual profitability.
Before we get into it however, I want you to understand that there has to be a mindset shift here regarding Google’s automation and PMax.
Performance Max isn’t the enemy. It’s a powerful but indiscriminate engine. It operates not on trust, but on the quality of its inputs. The more precise your inputs (feeds, exclusions, creative), the more disciplined your outputs. Think of your role less as fighting automation and more as architecting the guardrails that force the AI to align with your profit margins.
I had a client show me a PMax campaign with a 600% ROAS. But when we looked at the reporting we saw $3,000 in a month going to low-intent YouTube placements. That’s when I realized the PMax black box isn't hiding performance; it's hiding waste. Your job is to find the hidden lever and adjust and be aware of what’s happending.
1. The "Video Trap" (Are you buying Shopping or YouTube?)
In the old days, you had a Shopping Campaign and a YouTube Campaign. You controlled the budget for each.
In PMax, Google blends them.
Often, when I audit new accounts, I see PMax campaigns that think they are driving sales, but are actually dumping 40% of the budget into low-intent Video views because they are cheaper than Search clicks.
Cheap views can look good on paper, but remember: CTR isn’t the metric that matters.
The Audit: Go to your Campaigns tab and modify your columns to include "Avg. CPV" (Cost Per View).
The Red Flag: If you see data in this column for your primary PMax campaign, you are paying for video views.
The Fix: Ask yourself if this campaign is supposed to be for bottom-of-funnel conversion. If yes, that spend is likely wasted. You may need to move to a "Feed-Only" PMax structure or tighten your asset groups to force Google to focus on the Shopping feed rather than forcing video impressions.
I think about this as budget stewardship in PPC strategy work.
Every dollar in your ad account is a resource you control.
PMax will spend it, but you decide the guardrails.
By auditing placements and tightening structures, you transform wasted spend into incremental revenue.
The strategist’s role is not to resist automation, but to ensure it’s accountable.
2. The URL Expansion Leak
PMax has a feature called URL Expansion. Think of it as Dynamic Search Ads (DSA) on steroids. Google spiders your site and decides where to send traffic.
The theory? It finds new pockets of demand. The reality? In 2025, it often sends expensive clicks to your "Terms and Conditions" page, your blog posts from 2019, or out-of-stock product categories.
This kind of misallocation is similar to common agency tactics that drain ad spend.
The Audit: Navigate to the PMax Campaign > Listing Groups, but look for the "Landing Page" report (or use the custom report editor).
The Red Flag: Sort by cost. Are your top landing pages actual Product Detail Pages (PDPs) or Collections? Or are you paying $3.00 a click for traffic to your "About Us" page?
The Fix: Aggressively exclude non-commercial URLs. If URL Expansion isn't beating your standard campaigns, turn it off. Do not let the algorithm "explore" on your dime without boundaries.
Google has been prioritizing transparency and we saw this in the 2025 Roadmap.
The black box metaphor is useful, but misleading. PMax isn’t opaque, it’s just layered. With the right reports and checking the landing pages, you can peel back those layers and see exactly where your budget flows. Transparency isn’t given; it’s built through disciplined auditing.
3. The "Mobile App" Money Pit
This is the silent killer of ROAS in 2025. PMax loves to serve Display ads inside mobile apps and games (think Candy Crush or utility apps). These placements generate massive amounts of accidental clicks.
Accidental clicks are a reminder that qualified traffic beats vanity metrics.
Google’s algorithm sees a "click" and thinks it’s doing a good job. You see a bounce rate of 99% and zero conversions.
The Audit: Go to Reports > Other > Performance Max campaigns placements.
The Red Flag: Look at where your impressions are coming from. If you see a long list of mobile applications, you are burning cash.
The Fix: You cannot easily exclude these in the PMax settings menu anymore. You need to apply account-level placement exclusions for app categories. If your agency hasn't done this, they are letting Google inflate your CTR with junk traffic.
4. Moving Beyond the Interface: The Scripting Era
The native Google Ads interface in 2025 is still intentionally vague. It groups "Search" and "Shopping" into broad buckets.
To truly manage a large portfolio, you must move beyond the interface. I utilize custom scripts (like the widely adopted Mike Rhodes PMax script) to visualize spend allocation.
I need to know:
How much spend went to Shopping (High intent)?
How much went to Video/Display (Top of funnel)?
How much went to Brand Search (Cannibalizing your own organic traffic)?
If your current report just says "PMax: 500% ROAS," but 80% of that was Brand Search you would have gotten anyway, the campaign isn't working but it's taking credit for work you already did.
This requires a paid search strategy focused on the long-term instead of immediacy.
Short‑term ROAS can be deceptive. A campaign that looks efficient today may be leaning heavily on brand search or accidental clicks. True strategy means asking: Is this spend creating new demand, or just recycling what I already own? That distinction is where profitability lives.
Something I said the other day on LinkedIn that others in the industry loved was: “You can’t scale a lie”.
Summary: Control the Inputs, Audit the Outputs
Automation does not mean abdication. As the platform becomes more automated, the role of the PPC Strategist shifts from "bidder" to "auditor" and "architect."
This shift mirrors a bigger industry change: why the traditional agency model is failing.
If you suspect your PMax campaigns are leaning too heavily on brand traffic, leaking budget into mobile games, or prioritizing views over sales, it is time for a forensic audit.
Automation doesn’t absolve responsibility. It amplifies it. By stepping into the role of auditor and architect, you reclaim control. Waste exists, but you are not powerless. You are the one who decides whether PMax is a liability or a growth engine.
Because at the end of the day, building campaigns is easy—doing it well takes skill.
🔍 Ready to Audit Your PMax Campaigns?
Don’t let wasted spend hide in the black box. Get a forensic audit of your Performance Max campaigns and see exactly where your budget is going — and how to fix it.
Book Your Audit Now