The concept of limited availability can have a huge influence on our behaviour. Who hasn’t bought a broccoli/mango soft drink, a lace parka or a cat detangler just because they’ll never have the chance to do so again?
Well. Perhaps it’s just me.
Researchers have been investigating the effect of scarcity for decades. In a 1975 study, university students were asked to sample a chocolate chip cookie then rate how much they liked it. Some students saw only two cookies in the sample jar, while others saw 10. Still others saw 10 cookies but the experimenter then traded that jar for one that contained only two (either because he had accidentally taken the wrong jar or because other study participants had been eating more cookies than expected).
The cookies were all the same, but the results were very different among the groups of participants. The ones who saw only two cookies liked them better than the ones who saw 10. However, the ones who saw their 10-cookie jar swapped out for a two-cookie jar liked them even more – and those who were told this was because other participants had been eating too many cookies liked them most of all.
(I think it’s interesting that they didn’t rate the cookies as tasting better – there were no differences among the various groups on ratings of taste. Yet the answers to “If given the opportunity, would you like to eat more of this item?” and “How attractive is this item?” were very different.)
It appears that the effect of scarcity is greatest when the scarce item is unique, available only in limited quantities, or available only for a limited time. Part of the reason for this is that we’re more sensitive to the possibility of loss than the possibility of gain (see this post for more details). Auctions play to this as effectively as “limited quantity” and “today only” sales do.
Using the scarcity effect to sell things can be pretty sleazy, especially if the goods aren’t really limited. It doesn’t have to be, though. You can tell your clients or customers what is genuinely unique or unusual about your goods or services. You can point out to potential volunteers that the opportunity to participate in a project like yours doesn’t come along every day. You can offer the chance to be “one of the first” members or donors, which can be a status symbol.
You can use scarcity ethically. Because you don’t want to be responsible for the resentment and disappointment someone will feel when a sense of scarcity leads her to buy a broccoli/mango-flavoured parka detangler. Or whatever.