In a funnel, the goal is to turn a prospect into a valuable customer by passing through multiple touchpoints to ultimately perform a specific action, such as completing an order.
Pictorially imagined, for example, quite a lot of prospects come into the funnel through Facebook ads. In the process, prospects may bounce during the buying process, meaning they jump out of the funnel again. However, the prospects who have completed an order become customers and figuratively come out the bottom of the funnel.