Key Summary
- PMax prioritises scale and probability, not precision
- Negative keywords in PMax act as guardrails, not hard walls
- Intent drift is a feature of automation, not a temporary bug
- Search still wins when lead quality and exclusions matter
- PMax should often support Search, not replace it
What We’re Seeing in Live Accounts
Across a range of industries, we’ve observed:
- Search terms that don’t match the client’s core offer
- Queries reappearing after being excluded
- Traffic that looks fine in-platform but fails downstream
Importantly, this isn’t about poor setup or lazy management. These accounts:
- Have clear conversion tracking
- Have documented negative keyword lists
- They are actively monitored and refined
Yet the behaviour persists.
The pattern is consistent enough that it’s no longer anecdotal. It’s systemic.
Why This Is Happening
1. Performance Max Optimises for Probability, Not Strategy
PMax doesn’t think in keywords. It thinks in terms of conversion likelihood.
If Google’s model believes a query is adjacent to a converting user, it may still serve, even when that query:
- Sits outside the intended positioning
- Produces low-quality leads
- Has been excluded for commercial reasons
In PMax, negatives guide the model. They don’t always stop it.
2. Intent Drift Is an Expected Outcome of Automation
PMax is designed to:
- Expand coverage
- Find new demand
- Test edges of relevance
That’s useful when:
- Margins are strong
- Lead quality variance is acceptable
- Sales teams can absorb noise
It’s a problem when:
- Intent needs to be tightly controlled
- Certain searches are wrong, not just inefficient
- Clients feel the impact after the click
What we’re seeing isn’t the system malfunctioning. It’s the system doing exactly what it was built to do.
3. Google Is Forcing a Trade-Off
Quietly, but clearly, Google is pushing advertisers toward a choice:
- Automation and scale, with less visibility and control
- Manual structure and intent, with clearer guardrails
There is far less middle ground than there used to be.
Why We’ve Moved Some Clients Back to Search
Standard Search campaigns still offer something PMax doesn’t:
- Hard negative keywords that actually stick
- Query-level transparency
- Clear intent segmentation
- Easier explanations to clients and sales teams
For businesses where:
- Lead quality matters more than volume
- Certain searches must never trigger
- Budgets need to be efficient, not exploratory
Search is still the better tool.
This isn’t a step backwards. It’s a strategic choice.
When Performance Max Still Makes Sense
We still use PMax when:
- Conversion signals are clean and consistent
- Margins can tolerate exploration
- The offer has broad commercial relevance
- Search coverage is already strong
In these cases, PMax works best as:
A scaling layer on top of solid Search foundations
Not a replacement.
Bottom Line
Performance Max is a powerful system. But it is not a precision instrument.
When intent control, exclusions, and lead quality matter, Search remains critical.
Our job isn’t to use the newest product. It’s to use the right one.
