Endowment Effect

No, it's not the impact sustained Viagra use has on your social life. Instead, it relates to the psychological attachment people get to things they already own.

You own a junky old car, a 1994 Buick Regal that does nothing but leak various fluids into your driveway. It's worth maybe $100 in scrap value. But you won't sell it.

A neighbor offers you $200 just to get rid of the eyesore. But you say, "no." You've had the car for more than a decade. You love it. You won't sell. Eventually you just push it into the garage and consider setting up a Buick Regal museum to house it.

Someone hears about your Regal Museum plans and offers to sell you his 1994 Buick Regal. It's almost exactly the same as yours. He offers it to you for $200. You laugh in his face. "That hunk of junk is barely worth a hundred bucks for scrap," you scoff.

The discrepancy in those opinions represents the endowment effect. You own the car. Someone offers you $200. You turn it down.

But, reverse the situation, with you having $200 in cash and someone else having the car, and you'd rather have the cash. Just having the item makes it feel more valuable. You want more to sell it than you would pay to buy it.