Tom Sawyer effect

Scarcity breeds desire: “In order to make a man or a boy covet a thing, it is only necessary to make the thing difficult to attain.”


  • Often it is sufficient to manufacture the feeling of scarcity without actually limiting supplies. For instance, the sentence “if operators are busy, please try again” has much more social proof than the sentence “operators are standing by take your calls,” because it implies high demand for the item being sold.
  • You can also create scarcity by limiting the time that something is available. The Humble Bundle games offers bring a set of well-liked independent computer games together into a pay-what-you-like deal, but only for a two-week period. Even if you hadn’t been planning on purchasing all of the games, or if you had already purchased one of them at full price, this limited-time offer provides a good incentive to get the whole bundle while the games are cheaper than they would otherwise be. This is a form of loss aversion that applies even before people have the product in hand. Paying full price for one of the games is now a “loss” in comparison to purchasing it as part of this bundle.


Tom Sawyer got other kids to work for him because he convinced them that it was a scarce event (“Does a boy get a chance to whitewash a fence every day?”) only open to select individuals with sufficient skill (“I reckon there ain’t one boy in a thousand, maybe two thousand, that can do it the way it’s got to be done”) and where demand was greater than supply (“If he hadn’t run out of whitewash he would have bankrupted every boy in the village”). Tom pushed all the right buttons that turn scarcity into desire.

How to use this pattern

  • Include the three elements of scarcity to ensure people desire your product:
    • Infrequency – make it clear that the offer or event is only available for a limited time.
    • Exclusivity – promote items that only certain people will qualify for (even if the qualification criteria are as loose as “has a pulse”).
    • Competition – show that there are others who are also interested in the scarce resource.