Shelf conversion follows shoppers from passing a category to looking at it, engaging with it and buying from it. Instead of a single ratio, it is read as a physical funnel with four steps, so each loss can be located.
Shoppermotion defines the steps by speed and by the matched ticket: traffic is the trips that passed the bay; visual contact is the trips that slowed below 45 cm/s in front of it; engaged trips stopped below 25 cm/s; buyers are the trips whose ticket contains a product from it. The conversion funnel article covers the full definition.
Each drop tells a different story. Low visual contact is a visibility problem (location, signage, facing). Low engagement after visual contact points to the shelf itself. A big gap between engaged shoppers and buyers means they were interested but walked away because of price, availability or choice overload. Those engaged trips without a purchase are counted as missed opportunities, and Category Pulse in Shoppermotion AI puts every category on a traffic and conversion matrix to expose the shelves that attract but do not convert.
In a flyer promotion analysed on our blog, out of 50,000 visitors 7,200 bought eggs while only 1,100 bought salmon. Eggs showed a high bounce rate because shoppers already knew the brand they wanted, while fresh salmon had many browsers checking the expiration date or appearance.