This technique corresponds with "lead scoring" in a B2B context. In short, you can prioritize the relevance of incoming sales leads based on their interactions with you. Usually, the three main criteria used include RFM (recency, frequency, and money). A prospect with recent interactions is more likely to buy from you. A prospect who's frequently "touched" you, i.e., opened emails, attended meetings, or fielded calls, is more likely to buy. A prospect who's already spent money elsewhere to solve the problem (or with you) are more likely to buy from you. This is already implemented in various CRM and email software packages.