When instant cake mixes were introduced in the 1950s, housewives were hesitant because they thought it devalued their labor. Manufacturers changed the recipe to require adding an egg. Richard Landers summarizes a new study that tested the tendency of people to value things they have created or built themselves:
Participants either inspected an IKEA pre-built box or assembled it themselves. Afterward, they were asked to bid on the box they had either seen or built. … [O]n average, participants bid 62% more when they built the box versus when they simply inspected it. On average, participants also self-reported liking the self-built box more than the inspected boxes.
The Dish 