Performance Max in B2B is professional malpractice

Last year a rep pitched me on Performance Max for the MECCO account. Said it would simplify campaign management and improve reach across Google's full network.

I ran it for 45 days as a test. Here's what I found when I dug into the placement reports:

Mobile games. YouTube videos aimed at teenagers. Parked domain display placements. Dozens of irrelevant Gmail ad impressions.

All of it blended together in a single campaign reporting "strong ROAS."

The ROAS was strong because the brand search component was working. The display and video components were subsidized noise.

What PMax actually is

Performance Max is a campaign type that bundles search, display, YouTube, Gmail, Discovery, and Shopping into a single campaign. You provide asset groups (headlines, images, videos, descriptions) and an audience signal. Google decides where and when to serve your ads.

You cannot separate the channels. You cannot isolate the budget between search and display. You get one blended view of "performance."

In e-commerce this can work. You have a large audience. The product has broad appeal. Volume is high enough that the algorithm has data to optimize against.

In industrial B2B manufacturing, you have:

• A tiny addressable market
• Very specific buyers who are only online in a few places
• Long sales cycles the algorithm can't see
• No meaningful YouTube or Display intent signals

The specific problem

PMax needs to spend. If it can't find enough qualified search traffic (which it often can't in niche B2B), it will spend on display and video placements that are cheap and abundant.

Your budget goes to YouTube pre-roll ads that procurement managers skip after five seconds. Display banners on sites that aren't even close to relevant. Mobile app ads.

All of this looks like "impressions" and "reach." None of it is a VP of Engineering looking for a laser marking solution.

Meanwhile, your brand search data is powering the ROAS metrics that make the campaign look like it's working.

What to do instead

If you're running Shopping campaigns, standard Shopping is still the better option for most B2B advertisers. You control placement. You control match type.

For lead gen, use standard Search campaigns. Keep control of where your ads appear. Use exact match. Build proper negative lists.

If you want display or YouTube, run them as separate campaigns with separate budgets so you can actually measure performance.

PMax is a black box that benefits Google. It's not built for the precision that high-ACV B2B accounts require.

Turn it off. Go back to boring, controllable, auditable campaigns.

Boring campaigns that you understand will outperform exciting campaigns that you can't audit. Every time.