Clicks, searches, dwell time, add‑to‑cart, purchases, ratings, returns, location, device, and even the time of day combine into a living profile of intent. None is decisive alone; together they sketch urgency, budget, taste, and context, letting systems respond in minutes rather than months.
A catalog with hundreds of thousands of items can paralyze choice. Ranking brings order by promoting likely wins while keeping room for discovery. The goal is not one perfect answer, but a helpful shortlist that evolves as you browse, compare, and reconsider.