Motivation and habit
IKEA effect
Also called Investment, Effort justification
People value what they've put effort into, so things they help build or set up feel worth more to them.
People who assemble something themselves value it more than the same thing built for them, as long as they finish it. The effort becomes part of the value.
In products, small investments of time, content or setup make people more likely to return: a customised dashboard, a library of saved items, followers they've built up. Each investment makes the product better for them and harder to leave.
In practice
A note-taking app becomes harder to leave with every note, tag and link someone adds, because their own structure lives there.
Common mistake
Asking for effort before people see any value. The effect only works once the effort pays off; unfinished, frustrating setup does the opposite.
Where it comes from
Named by Michael Norton, Daniel Mochon and Dan Ariely in 2012, after experiments in which people valued furniture and origami they had made themselves. Nir Eyal calls this step investment in his hook model.