Performance Max (PMax)

With Performance Max the advertiser supplies a goal, a budget, some text, images and video, and Google's systems decide where each ad runs and what to bid. It is the most hands-off way to advertise on Google.

It touches search arbitrage from both sides. On the sell side, PMax campaigns can serve on the search partner network, so some of the ads that appear on an arbitrageur's search feed pages were placed there automatically. For years advertisers complained they could not see this. Google has since added site-level placement reporting and, in January 2026, channel reporting that breaks out search-partner performance, which makes placement exclusion of weak partner sites easier.

On the buy side, a few arbitrageurs use PMax to acquire visitors, though Google Demand Gen gives more control over creative and surfaces. In both directions the lesson is the same: PMax bids on predicted conversions, so partner traffic that does not convert for advertisers is steadily bid down.

Think of it like this

It is like handing a travel agent a budget and saying "get me the best holiday". You gain convenience and lose sight of exactly where the money went.