Buyer's remorse is the sense of regret after having made a purchase.
Regret is a negative conscious and emotional reaction to personal past acts and behaviors.
Buyer's Remorse: 7 Cars Owners Regret | Consumer Reports by Consumer Reports
It is frequently associated with the purchase of an expensive item such as a car or a house.
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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.
In psychology, cognitive dissonance is the mental stress experienced by a person who simultaneously holds two or more contradictory beliefs, ideas, or values; when performing an action that contradicts existing beliefs, ideas, or values; or when confronted with new information that contradicts existing beliefs, ideas, and values.
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.