Create a vacuum, don't fill it
On the path from awareness to a sale, the marketer has to create a vacuum.
The goal of that short film or that sales letter or that invitation to a seminar shouldn't be to answer every question and completely describe what's on offer. No, effective marketing amplifies awareness of a problem or an opportunity, a problem the product or service solves or an opportunity it creates.
I know it's tempting to sell with bullet points and an overwhelming amount of data. It gets you off the hook and requires little in the way of creativity or guts. Storytelling requires both.