Whether you're in B2B or B2C, and whether you're in Sales or Marketing, you have a sales funnel you need to manage. That's simply the list of suspects and prospects who are somewhere between aware and closed.
The point is that if you don't have a reliable process for getting suspects into your funnel, moving prospects through your funnel, and pushing customers out of your funnel, you're going to fail at your job.
The Rest of the Story...
Ironically, most companies completely mangle this concept because they don't understand the classification system. The way it's supposed to work is that "C" prospects are new to the funnel, "A" prospects are closest to closing, and "B" prospects are somewhere in the middle.
Instead, many companies classify their biggest (and therefore assumedly most important) prospects as "A" prospects, their smallest (and therefore least important) prospects as "C" prospects, and the others somewhere in between.
Riddle me this: How do you move a prospect through such a funnel, from C to B to A? By making them bigger and more important?