When setting performance targets for paid media, stakeholders often default to a simple goal: more sales at a lower cost per acquisition. It’s a natural business instinct — but turning that into an effective optimisation strategy can create friction.

Why? Because the actions required to improve efficiency are often directly at odds with those needed to increase volume.

Let’s explore what that means in practical terms.

Improving Efficiency

Whether your goal is a stronger CPA or higher ROAS, improving efficiency generally requires pulling back. Key actions include:

• Pausing low or non-converting keywords with poor return on investment

• Reducing bids to lower CPCs, often sacrificing position, CTR, and impression share

• Cutting upper-funnel campaigns that build awareness but don’t convert directly

• Tightening bid strategy targets, lowering costs but also reducing traffic

The result: lower spend and improved cost efficiency, but with fewer clicks and conversions overall.

Pushing for Volume

On the other end of the spectrum, pursuing more volume means expanding aggressively, often at the cost of efficiency. That might involve:

• Broadening your keyword set to capture more reach

• Raising bids to win more impressions and clicks

• Leveraging wide-reaching tactics like Performance Max, DSA, and broad match keywords

• Supplementing search with display campaigns to drive incremental demand

The result: more traffic and visibility, but higher costs and diminishing returns per conversion.

So, Which Strategy Is Right?

Here’s the million-pound question: What should your CPA or ROI target actually be?

The answer depends entirely on your business goals, margins, and competitive environment. As a starting point, aim for a middle ground that enables testing and learning. From there, refine based on results.

Your target should be:

• Aligned with business objectives – Are you focused on growth, profitability, or market share?

• Sustainable – Can the cost and volume be maintained long-term?

• Compatible with other marketing efforts – Your paid strategy should support, not compete with, broader campaigns

From this foundation, you can shift your targets to suit changing goals. For example, during sale periods with tighter margins, you might favour higher ROI over sheer volume.

As your business goals shift, so should your targets. A strategy that leans into volume may be ideal during periods of growth or market capture, while a sharper focus on efficiency becomes essential when protecting margins or responding to rising costs.