A pipeline lays out every live opportunity in columns by stage, for example enquiry, site visit, quote sent, negotiation and won. Each opportunity is a card that moves along as it progresses, so anyone can see what is coming and what is stuck.
It turns sales from a feeling into something you can examine. You can see how many quotes are outstanding, how long deals sit at each stage and roughly what the coming months may look like. Forecasts from a pipeline are estimates, not promises, and are only as honest as the stages are kept up to date.