The Shopping Cart Without Add-to-Cart — An Anomaly Worth Investigating

The GA4 Shopping Cart page view without a corresponding add_to_cart event is an anomaly. Possible explanations: (1) The visitor bookmarked the cart page from a previous session; (2) The visitor typed the cart URL directly out of curiosity; (3) The add_to_cart event fired but GA4's JavaScript failed to capture it (client-side tracking gap); (4) A bot or crawler hit the cart URL. Each hypothesis has different implications for traffic quality assessment. The anomaly underscores the limitations of GA4 as an observation instrument: it captures client-side events but cannot distinguish human intent from automated access or curious browsing. This measurement limitation parallels the nudge system's inability to distinguish idling from observation.