For a sales bulge to qualify as a sales prospect, or equivalently to movement Buy Email Leads a over from the process step sales head to the evolution sales prospect, qualification must be performed and evaluated. Typically this involves identifying by direct interrogation the lead's artifact applicability, availability of funding, and date frame for purchase. This is also the entry mote of a sales tunnel, sales funnel or sales pipeline.
Sales leads are a central element of the story of the movie Glengarry Glen Ross, about four embodied estate salesmen who want "the favorable leads" which will close more easily (result in closed sales, i.e. a financial transaction).