Why Chasing Cheap CPMs in Meta Ads Can Kill Your Top-of-Funnel Performance

At first glance, a low cost per thousand impressions (CPM) in Meta Ads can feel like a win.

More reach for less money — what’s not to love?

The problem: cheap CPMs don’t always mean better results. In fact, they can lead your top-of-funnel (TOF) campaigns straight into a dead end.

The Hidden Risk of Low CPMs

Meta’s ad delivery algorithm is designed to find the cheapest impressions for your budget and not necessarily the most relevant ones. When you optimise purely for low CPM, you can end up paying to reach:

• Bot traffic that inflates your numbers but never converts.
• Click-happy users who engage with anything but have zero buying intent.
• Low-intent scrollers who passively watch without real interest in your offer.

It’s reach without relevance and that’s not a recipe for revenue.

You’re Not Buying Reach. You’re Buying Relevance.

Even at the top of the funnel, your goal should be to feed Meta signals that matter. This teaches the algorithm what “quality” looks like for your brand.

Instead of optimising for impressions alone, focus on metrics that indicate real engagement:

1. Video ThruPlay – Tracks viewers who watch to the end (or at least 15 seconds), showing stronger interest.
2. Landing Page Views – Confirms people are clicking and loading your site, not just clicking accidentally.
3. Engaged Users – People who interact meaningfully with your content, from comments to shares.

The Bottom Line

Reach is easy. Relevance takes strategy.

When you train Meta to prioritise meaningful actions over cheap impressions, your TOF campaigns generate audiences that actually convert further down the funnel and that’s where the real ROI lives.