Performance Max: when yes, when no
Performance Max (PMax) is Google's flagship advertising format since 2022. It promises "AI-driven" optimisation across all channels — Search, YouTube, Display, Discover, Gmail. For retailers, this often genuinely works. For lead gen, it can be pure revenue drowning.
When PMax helps
Retail with quality product feed. If you have an e-shop with 500+ SKUs and each SKU has good images, descriptions, prices and availability, PMax combined with Shopping campaigns will earn money. The algorithm understands products and can match them with purchase intent in real time.
Broad catalogue with varying margins. PMax can prioritise products with higher margins if you allow it through "value rules" or set conversion value goals.
When PMax harms
Lead gen. PMax relies on conversion signals. If you have a lead form, the signal is weak and the algorithm cannot optimise it. You end up with expensive leads of poor quality.
Brand-heavy categories. PMax "claims" brand traffic — when someone searches for "Adlify", PMax inserts the brand keyword into its own campaign and attributes the conversion to itself, which would have happened without it. This distorts ROAS and lumps cheap brand traffic as its own achievement.
Practical recommendation
- Don't run PMax without Shopping campaigns. They form a partnership, not competition.
- Reserve brand keywords for a separate Search campaign with negatives in PMax.
- If you're lead gen — test Search + Demand Gen first, then PMax.
- Monitor cross-channel attribution. PMax likes to claim credit for what you'd have without it.