Exactly how the marketing channel works The earliest variation of a sales funnel that I'm able to find is this one from 1904 by Frank Hutchinson Dukesmith, editor of the Salesmanship publication Below, Dukesmith introduced the concept of four stages that result in a sale: Focus, Passion, Desire and also Conviction. Virtually half a century later, an advertising and marketing as well as sales executive in the pharmaceutical sector, Arthur F Peterson, released the complying with image in his publication, Pharmaceutical Selling, Detailing, and Sales Training: