Performance Max for Shopify: a setup that actually scales

Performance Max sells itself as 'just turn it on.' In practice the default setup is a black box that wastes the first $5K of spend on brand searches and remarketing you were already getting for free.

The feed is the campaign

PMax is more dependent on your product feed than any campaign type before it. Clean titles, real GTINs, custom labels for margin tiers — this is where 70% of the optimization happens.

Exclude brand. Always.

Add your brand terms as a negative keyword list at the campaign level. If you don't, PMax will harvest those clicks and report inflated ROAS while doing nothing incremental. We've seen accounts cut their reported ROAS in half after this single change — and their real revenue went up.