People tend to value things they have (partially) created or made themselves more than things made or designed by others. This effect is named after the furniture store IKEA, where purchased products often need to be assembled by the buyer. The IKEA effect has been known for a while, but in 2011 it was also officially proven through scientific research by researchers from the universities of Harvard, Yale, and Duke. The researchers demonstrated through various experiments that people value a product more if they have to (partially) perform labor to bring the product into existence. This phenomenon also occurs when the result is worse than if a professional had done it.
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