Google Just Took the Wheel on Your Ad Campaigns

Log into your Google Ads account this month and something might already be different, and you didn’t touch a thing.

Starting September 1, Google began automatically migrating every Search campaign using Broad Match or Automatically Created Assets into “AI Max,” with zero opt-out once the switch hits your account. Microsoft flipped on its own AI Max by default too. It’s not rolling out gradually to a test group. It’s happening to everyone, campaign by campaign, all September.

Here’s the number that should stop you mid-scroll: Google claims AI Max delivers a 7% lift in conversions. Independent analysis across 250+ retail campaigns found a 35% ROAS decline instead. That’s a 42-point gap between what the platform says is happening and what advertisers are actually measuring.

“But My Numbers Look Fine”

Maybe. Or maybe you just can’t tell yet, and that’s the real trap here.

AI Max doesn’t launch as a new campaign, so your campaign IDs, budgets, and bid strategies stay exactly where they were. What silently changes underneath is how your ads actually behave: broad match campaigns get “search term matching” turned on by default, expanding your reach to queries you never targeted, with rewritten ad copy, without anyone touching a setting.

Which means “this month’s numbers look decent” and “AI Max is genuinely working” have quietly become two different questions, and most brands don’t have a baseline to tell them apart.

The Quality Problem Nobody’s Talking About

It gets worse before it gets better. A study of over 414 million clicks found AI Max-enabled retail campaigns had a 5.28% invalid-traffic rate, versus 3.07% for standard campaigns, a 72% jump. You could be paying for more clicks that were never going to convert in the first place, and the dashboard won’t flag it for you.

What to Actually Do Before It’s Too Late

• Pull your search terms report now, before the migration reaches your account, so you have a real “before” to compare against
• Check whether you’re using Broad Match or Automatically Created Assets; if so, you’re in the migration path whether you’ve noticed or not
• Re-confirm your brand inclusions and negative keywords after migration; they’re supposed to carry over, but “supposed to” isn’t “verified”
• Track ROAS weekly, not monthly, through September; a slow bleed is easy to miss until it’s already cost you real budget

The Bottom Line

Nobody asked if you wanted an algorithm making more decisions about your ad spend. It’s happening anyway. The brands that come out ahead this month aren’t the ones hoping it works out. They’re the ones who checked before Google checked it for them.