Final answer:
The motivation to satisfy a need through a purchase is known as consumer demand or buyer's intent, and when a shopper gets a good deal, it is called consumer surplus.
Step-by-step explanation:
The purchaser's motivation to purchase the item in question to satisfy a need is called consumer demand or buyer's intent. When a shopper perceives a good deal on a product, the term an economist might use is consumer surplus, which refers to the benefit or satisfaction a consumer feels when they pay less for a product than what they were willing to pay. The availability and clarity of information play a crucial role in shaping the buyer's belief about the satisfaction that a product or service will provide, influencing their purchasing decisions and the perception of getting a good deal.