The native Shopify Google Ads channel is a great onboarding tool. It gets Shopping live in 20 minutes and PMax running shortly after, with a feed that is mostly OK. For sub-R10k monthly media that is enough. Above that, the cracks show: PMax with no deliberate signals, Shopping feeds with taxonomy and attribute gaps that quietly cap impression share, no Search support so the funnel only catches buyers already at the bottom of the stack, no brand protection so a competitor outbidding you on your own name eats your CPA, and remarketing that retargets every visitor with the same banner.
The fix is not a different platform; it is the full funnel run on top of the native channel. We keep the Shopify Google integration for what it does well (the data sync, the GA4 link, the customer-list sync) and we layer non-brand Search, brand protection, segmented remarketing, and proper PMax asset groups on top. Most stores see a step-change in performance once Search, brand, and audience-segmented remarketing are running in parallel with the Shopping and PMax that was already there.
PDP work compounds on top of media. A 0.5 percent lift in PDP conversion rate is the same outcome as a 14 percent lift in media efficiency, only it persists across every channel forever. We test PDPs natively in your theme so the change applies to your organic traffic, email, and direct traffic as well, not just paid. That is the second source of compounding lift, and most agencies leave it alone because PDP work is messier than dashboard work.