There are a lot of wildly different defections for a sales funnel. Some describe it as the sales process your prospects go through to become a customer. Other definitions include a marketing process to create prospects. It can also be used interchangeably with Sales Pipeline to describe the prospects you are currently engaged with (i.e. the size of your funnel). The Funnel metaphor is used based on the premise that you need more prospects in the top of your funnel (the start of your sales process), a number that will be whittled down as they move through the process to ultimately becoming a customer. The metaphor is misleading, in that prospects never move through a sales process as easily as liquid through a funnel. Regardless, most salespeople lack from sufficient new prospects entering their sales funnel. Proper Sales Funnel management tracks quantity, quality and velocity of activity into and through the funnel.