Buyer's remorse

Buyer's remorse (or buyer's regret) is the sense of regret after having made a purchase. It is frequently associated with the purchase of an expensive item such as a car or a house. It may stem from fear of making the wrong choice, guilt over extravagance, or a suspicion of having been overly influenced by the seller.

Buyer's remorse is thought to stem from cognitive dissonance, specifically post-decision dissonance, that arises when a person must make a difficult decision, such as a heavily invested purchase between two similarly appealing alternatives. Factors that affect buyer's remorse include resources invested, the involvement of the purchaser, whether the purchase is compatible with the purchaser's goals, and what positive or negative evidence the purchaser encounters post-purchase that confirms or denies the purchase as a good idea.

The anxiety may be rooted in various factors, such as: the person's concern that they purchased a current model now rather than waiting for a newer model, purchased in an ethically unsound way, purchased on credit that will be difficult to repay, or purchased something that would not be acceptable to others.

In the phase before purchasing, a prospective buyer often feels positive emotions associated with a purchase (desire, a sense of heightened possibilities, and an anticipation of the enjoyment that will accompany using the product, for example); afterwards, having made the purchase, they are more fully able to experience the negative aspects: all the opportunity costs of the purchase, and a reduction in purchasing power.

Also, before the purchase, the buyer has a full array of options, including not purchasing; afterwards, their options have been reduced to:

Buyer's remorse can also be caused or increased by worrying that other people may later question the purchase or claim to know better alternatives.

The remorse associated with some extreme shopping activity may be, again, a sign of some deeper disquiet. However, normal "buyer's remorse" should not be confused with the complex emotional dynamics of "shopaholic" behavior, just as a binge on a special occasion should not be confused with a serious eating disorder such as bulimia.

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Wikipedia