Sales is focused on the individual, and marketing is focused on a unity of individuals. Sales can quickly bridge “the customer gap.” In sales, you are talking to a single individual, synchronizing the thought sequence.
In marketing, you are talking to a representative individual, a collective, and you must use a message that is general enough to appeal to that group. Specificity converts, and marketing will always have limitations to its absolute specificity. The gap — the customer gap — comes from not knowing how the representative individual is thinking. We market only when we cannot sell.