Economic buyer
The economic buyer is the person with the authority to release budget and give final approval on a purchase. They can say yes when everyone else can only say no, and they care less about features than about outcomes: return on investment, risk and how the spend fits their priorities. In a complex deal they're often not the person you first speak to, who may be a user or evaluator without spending power.
For a founder, identifying and reaching the economic buyer is decisive. A deal that looks healthy but has never touched the budget holder is a deal that can evaporate at sign-off. You don't always need to sell to them directly, but you do need to know who they are, what they measure success by, and to equip your champion to make the case in their language. The most common stall in B2B selling is a great relationship with someone who simply can't authorise the spend.