In IKEA, the long tail effect is a cognitive bias, and a dollar makes you feel that you have got a big bargain. 1 yuan ice cream, 6 yuan hot dog? Let you have an illusion: in such a big shopping mall, ice cream is almost free, so other goods should be very cheap, so cheap that you lose your mind.

The root of the long tail effect is to emphasize "personalization", "customer power" and "small profit and big market", that is, to make little money, but to make a lot of people's money.