What principle explains that people want more of what they can have less of?

The principle that explains that people want more of what they can have less of is the concept of scarcity. Scarcity implies that when resources, opportunities, or items are perceived to be in limited supply, their value increases in the eyes of individuals. This phenomenon results in heightened desire and urgency to acquire these scarce items since people naturally prioritize what seems less available.

In contexts such as marketing, the idea of scarcity can drive consumer behavior significantly; for example, limited-time offers or exclusive access to products often lead to increased demand and faster purchasing decisions. This response is rooted in psychological behaviors where the fear of missing out leads individuals to act more decisively when they believe something is at risk of being unavailable. Hence, scarcity effectively influences decision-making and enhances the desirability of items or opportunities.