We often come across this sort of alert while shopping online. It tries to tell us the products in stock is limited and you must buy it now! The persuasive tactic used here is called ‘scarcity’.
Advertising with scarcity appeals leads to enhanced value perception, which in turn increases purchase intention (Eisend, 2008).Verhallen and Robben (1994) conducted an experiment that demonstrated this effect of‘scarcity’on perceived value perception.
In their first experiment, the effect of product availability on consumer’s preference, uniqueness judgments, and cost evaluation of recipe books. There were four conditions of product availability, which included unlimited availability, limited availability due to popularity, limited availability due to limited supply and accidental unavailability.
As shown in the figure below, the results showed that participants preferred a book of limited availability due to market conditions (i.e. Popularity and limited supply) to books that were accidentally unavailable or of unlimited availability. This effect was most significant when the unavailability was due to both popularity and limited supply. Also, books of limited availability due to market circumstances were perceived as more costly and more unique than books that were accidentally unavailable or unlimited. (Note: social constraint shown in the figure below means the presence of other participants.)
In terms of my image, only 3 left in stock, if I cannot order immediately, I would probably miss it forever. Also, since they are samples, they must be special. Both of these reasons are likely to enhance my perceived value of this product, in turn, I will be more likely to purchase it.
Eisend, M. (2008). Explaining the impact of scarcity appeals in advertising: The mediating role of perceptions of susceptibility. Journal of Advertising, 37(3), 33-40.
Verhallen, T. M., & Robben, H. S. (1994). Scarcity and preference: An experiment on unavailability and product evaluation. Journal of Economic Psychology, 15(2), 315-331.