IKEA Effect
The IKEA Effect is the cognitive bias in which people place a disproportionately high value on objects they have partially created or assembled, regardless of the objective quality of the result. Documented by Michael Norton, Daniel Mochon, and Dan Ariely (2012), it shows that labour investment creates attachment and inflates perceived value — explaining why self-assembled furniture feels more special, why homemade food tastes better, and why people overvalue their own creative contributions.