Scaling Google Ads
might be the wrong move
for growth
Your performance marketing agency won't tell you this - but the spend relationship between channels is a far superior lever to growth than 90% of in-platform tests and tweaks. Scaling the wrong channel doesn't just plateau. It actively shrinks your new customer pool.
Understanding whether a channel is generating demand or simply capturing it changes everything about where your next pound of ad spend should go.
The spend relationship between channels is a far superior lever to growth than 90% of in-platform tests and tweaks.
Channel roles: demand generation vs demand capture
Every channel in your marketing mix plays one of two roles. It either generates demand - introducing your brand to someone who wasn't previously in-market - or it captures demand that already exists, intercepting users at the moment they're ready to buy.
In reality, multiple channels will claim credit for the same conversion through click-based attribution. These attribution models operate in silos - each channel reporting its own version of events, none of them telling you the full story. But only one channel would have done the heavy lifting upstream: convincing the user to start this journey in the first place.
It's those initial first-clicks that matter. Scaling the channel that provides demand generation - not the demand capture channel - is how you keep your new customer pool growing rather than shrinking.
Usually, it's Meta. It can be Google Ads. It can be Organic. But more often than not, the demand generator is Meta or paid social - channels that reach people before they go looking.
Google Ads, particularly non-brand Shopping and Search, typically sits on the capture side. It meets users where demand already exists, not where it's created.
What happens when you scale the wrong channel
Scaling Google Ads in this scenario means scaling the channel that captures demand - essentially scraping the bottom of the barrel. You're paying to intercept a small, fixed pool of users who were already going to look for your product. The pool doesn't grow just because you increase your bid.
That's supply and demand at work. If you continue to push spend into the capture channel, the law of diminishing returns kicks in and every sale becomes more expensive to acquire. You end up paying over the odds - and often unprofitably - to capture sales that would have come through anyway at a lower cost.
The result is predictable: unprofitable sales, a rising NCAC, and a shrinking new customer base. Not a good board report. The irony is that your ROAS might look fine - because you're capturing warm, in-market users efficiently. Meanwhile the cold audience pool that feeds your long-term growth is quietly drying up.
Further reading
New customer acquisition is stalling — check these 5 things today
New customer volume flat or declining? Five diagnostic checks to identify exactly what's causing the stall in your Google Ads account.
How to actually calculate your NCAC
New customer acquisition cost is the metric that matters — here's how to calculate it correctly and use it to make better decisions about where your budget goes.
The actual KPIs your Google Ads agency should focus on (hint: not ROAS)
Why ROAS is the wrong metric to optimise for, and which KPIs actually tell you whether your account is driving profitable growth.
Why your prospecting budget is being spent on retargeting
The hidden way Google Ads silently reallocates your cold audience spend towards warm retargeting audiences — and what to do about it.