The endowment effect showcases loss aversion by demonstrating how ownership leads individuals to perceive greater value in what they possess compared to its market value. Endowment effect is the tendency for humans to place more value on the things they own and therefore demand more to give up that item than they would acquire it. The endowment effect is a well-documented phenomenon in which people value a good they own more than an identical good that they do not own.

Michael platt defines the endowment effect as the phenomenon when people are often reluctant to trade what they have for what they do not have, even when doing so is objectively … In a valuation paradigm, people's maximum willingness to pay (wtp) to acquire an object is typically lower than the least amount they are willing to accept (wta) to give up that same object when they … The endowment effect is a principle in behavioral psychology that describes the tendency of people to value an object that they own higher than they would value if they didn’t own it.