One weakness in today's digital ad targeting that advertisers massively underestimate is how quickly user intent shifts within a single session. Most systems treat intent like a stable label, even though people browse, compare, get distracted, and completely change direction in minutes. Watching behavioral paths instead of isolated clicks reveals when ads are shown after the moment the decision has already evolved. It's similar to reading conversation flow rather than single keywords, because context drift quietly breaks targeting accuracy. Logs of journey sequences act like heatmaps, exposing where relevance fades or misfires across touchpoints and devices.