The default GA4 setup on a Shopify store usually undercounts conversions the moment iOS privacy settings, ad blockers, or cookie consent choices strip out client-side tracking which means the dashboard everyone’s making decisions from is often missing a meaningful chunk of real revenue before anyone even opens it. Server-side tracking through GTM closes that gap by capturing events directly from Shopify’s backend rather than relying on a browser to fire a pixel correctly, but it only works if it’s configured to match Shopify’s actual checkout and order events instead of a generic ecommerce template. Attribution gets murkier the more channels are involved: a customer might discover a brand through an organic blog post weeks before converting off a retargeting ad, and without proper multi-touch modeling, that ad gets 100% of the credit while the content that actually created the demand gets none which quietly biases budget decisions toward the channel that’s easiest to measure, not the one doing the most work. The same blind spot hits organic traffic broadly: without clean event tracking, it’s hard to tell whether SEO rankings are actually converting or just accumulating impressions that look good in a rank tracker but don’t move revenue. Clean data doesn’t just report performance it decides which channels get more budget next month, so getting it wrong compounds in the wrong direction.