Quick Answer: Performance Max inflates conversion counts in two ways: by claiming credit for branded search traffic it didn't generate (brand cannibalization) and by counting view-through conversions from users who saw a PMax ad and later converted through a completely different channel. Neither represents new customers. The fix is to isolate branded traffic, switch to click-through conversions only for your optimization target, and reconcile your Google Ads dashboard against your CRM.
What "Fake" Conversions Actually Means
When practitioners call PMax conversions fake, they don't mean the conversion events don't fire. They fire. Google counts them. They show up in your dashboard.
What's fake is the attribution — the claim that PMax caused those conversions.
There are two mechanisms at work. Understanding both is what separates an account that's actually growing from one that's running an expensive loop of self-congratulation.
Mechanism 1: View-Through Attribution
Performance Max runs across every Google-owned channel: Search, YouTube, Display, Discover, Gmail, Maps. On many of those channels, people see your ad but don't click. They scroll past a YouTube pre-roll. They glimpse a Display banner while reading an article. PMax records an impression.
If that same person later buys something — through organic search, a direct visit, a referral link, email, anywhere — PMax claims that conversion. It calls it a "view-through conversion." The logic is that the ad impression influenced the purchase, so the campaign deserves credit.
This is where it gets problematic. The view-through conversion window in PMax can be up to 30 days. During that 30-day window, any conversion that person completes counts. They don't have to click your ad. They don't have to have any conscious awareness that they saw it. The impression is enough.
A Google rep privately acknowledged this directly: "most PMax conversions are view-through when not brand included."
Read that again. When your PMax campaign includes branded traffic, the majority of its reported conversions may be from people who saw a Display or YouTube ad and then searched for your brand by name and converted through what was essentially an organic or branded search visit. PMax didn't acquire a new customer. It watched one show up and put its name on the clipboard.
Mechanism 2: Brand Cannibalization
The second mechanism is more visible once you know to look for it. PMax, without explicit brand exclusions, will bid on branded search queries — people searching your company or product name. These queries convert at extremely high rates. They're easy conversions. Of course PMax gravitates toward them.
The result is that your PMax campaign accumulates conversions from branded searches at high efficiency, while your dedicated branded Search campaign loses impression share. From the outside, PMax looks like it's performing well. Your overall account ROAS looks stable. But the underlying business question — are we acquiring new customers? — isn't being answered by any of those numbers.
It's basically paying yourself for clicks. Your brand already owned that demand. PMax just stepped in front of it.
How to Find Out If This Is Happening in Your Account
Step 1: Check your conversion type breakdown. In Google Ads, go to your PMax campaign, then segment by conversion type or look at the attribution breakdown. What percentage of conversions are view-through vs. click-through? If view-through is a significant portion of your totals, the campaign is crediting itself for traffic it didn't deliver.
Step 2: Check your branded campaign's impression share. Pull the Auction Insights report for your branded Search campaign and look at impression share trend over the past 90 days. If it's been declining since you launched PMax, the cannibalization is happening. PMax is taking branded queries your Search campaign would have won.
Step 3: Reconcile against your CRM. Take the number of PMax conversions from last month. Then look at how many new customers or qualified leads entered your CRM from Google-attributed channels in that same period. If the numbers are significantly different — say, 60 conversions in Google Ads and 15 in your CRM — the gap is your attribution problem.
Step 4: Run a brand exclusion test. Add your brand terms as negative keywords at the account level so PMax cannot serve on branded queries. Run for four weeks. Compare PMax conversion volume and revenue against the prior period. If PMax volume drops significantly but CRM-confirmed revenue stays flat, you've confirmed the cannibalization.
What Actually Counts as a Real PMax Conversion
A conversion that PMax is genuinely responsible for looks like this:
- Someone who had no prior relationship with your brand
- Saw a PMax ad on a non-branded query
- Clicked through to your landing page
- Completed the conversion action in that session or within a short attribution window
- Shows up in your CRM as a new lead or customer
This is incremental. This is new demand. This is what you're paying for.
The version where someone searches your brand name after seeing a YouTube ad three weeks ago is not incremental. They were already on their way to you. PMax is just collecting a toll.
The Fix
Remove view-through conversions from your primary optimization target. In your conversion settings, you can exclude view-through conversions from the actions you optimize for. This means PMax optimizes toward click-through conversions only — actual clicks that converted.
Exclude brand at the account level. Add your brand terms as a negative keyword list applied across the account, not just the PMax campaign settings, which are inconsistently enforced. This forces PMax to find non-branded demand or not spend.
Use offline conversions as your optimization target. Import qualified leads or closed sales from your CRM as offline conversions. Set PMax to optimize toward these instead of form fills or website events. This gives the algorithm a signal based on real business outcomes, not the widest possible conversion net.
Run a separate branded Search campaign. Keep branded traffic isolated in a Search campaign you control directly, with Target Impression Share bidding and an uncapped budget. This gives you clean data on branded performance and keeps PMax out of that inventory.
FAQs
Is Google lying about view-through conversions?
No — Google discloses that view-through conversions exist and are included in reporting. The problem is that most advertisers don't know to look for them or understand how significantly they can inflate totals. The disclosure is there; the default presentation buries it.
My agency says PMax is performing great. How do I know if they're right?
Ask them two questions: What percentage of PMax conversions are view-through vs. click-through? And how does the Google Ads conversion count compare to new customer count in our CRM for the same period? If they can't answer both, the performance claim isn't supported by real data.
If I exclude view-through conversions, will PMax performance look worse?
Yes, on paper — reported conversion volume will drop. Actual customer acquisition should stay the same or improve, because the algorithm will now optimize toward signals that represent real business outcomes. The dashboard numbers will look worse precisely because they were inflated before.
Do all Google campaign types have this view-through problem?
View-through conversions exist across campaign types, but PMax is especially prone to this issue because it actively runs on YouTube and Display — channels where impressions-without-clicks are the primary ad experience. Search campaigns, by contrast, are almost entirely click-through. If you're running a pure Search campaign, view-through attribution is a much smaller factor.