HighROASIsaSymptomofUnderinvestment
If your ROAS is consistently excellent, you are probably not spending enough. High efficiency at low volume often means you are capturing the easiest fruit and missing the next layer of profitable growth.
The High ROAS Paradox
A 10:1 ROAS sounds excellent. But what if you are only spending £10,000 per month? That £100,000 in revenue is great, but the question is: could you profitably spend £20,000 at 6:1? That would generate £120,000 in revenue.
High ROAS at low volume often indicates you are only capturing the most valuable, lowest-cost traffic. The algorithm is cherry-picking easy wins and ignoring everything else.
The Efficiency Trap
Optimising for efficiency alone is like a restaurant that only serves regular customers: profitable per transaction, but missing enormous opportunity from new diners who require slightly more effort to convert.
The Diminishing Returns Curve
Every advertising account has a diminishing returns curve. Your first pound of spend captures the most valuable traffic. Each subsequent pound is slightly less efficient.
The optimal spend level is not where ROAS is highest. It is where marginal ROAS equals your break-even threshold.
"Maximising average ROAS minimises total profit. Maximising profit means accepting lower efficiency at the margin."
Why ROAS Targets Cause Underinvestment
Setting a ROAS target tells the algorithm: "Only bid on traffic that meets this threshold." If your target is 6:1 and you are hitting 10:1, the algorithm is ignoring traffic that would convert at 7:1, 6:1, even 5:1.
- • All that 5:1 to 9:1 traffic is going to competitors
- • Your market share is smaller than it could be
- • You are leaving profit on the table
The Opportunity Cost of "Safe" Spending
Conservative ROAS targets feel safe. But safety has a cost:
Competitors Capture Your Customers
The traffic you are not bidding on goes to someone else. They acquire the customers you could have had.
Slower Growth Compounds
Each month of underinvestment means fewer customers, less data, and smaller remarketing audiences.
Finding Your Real Efficiency Frontier
To find optimal spend:
- Calculate your break-even ROAS based on actual margins
- Gradually increase budget while monitoring marginal ROAS
- Stop when marginal ROAS approaches break-even
- Accept that average ROAS will be lower than before
Reframing Success
Stop celebrating high ROAS. Start measuring total profit contribution. A 5:1 ROAS generating £500,000 profit is better than 10:1 ROAS generating £200,000.