Only X number of seats left at this price!
A persuasive tactic that I have seen utilised many times when I am purchasing flight tickets is that of informing the customer that there are only a few tickets left available at the price that is being viewed. This is persuasive in two manners. Firstly it places a perceived time constraint on the customer. The impression that is given is that the tickets are being sold at a fast rate, when in reality only the quantity is told, rather than the rate of sale. This time constraint encourages peripheral processing over central processing (Petty & Cacioppo, 1986), and is thus the message is more persuasive than if the customer was allowed longer to process the message. This increase in persuasiveness can then translate into a higher number of sales, even if the ticket being sold is not the most appealing.
The second persuasive tactic that is in effect is that by showing how few tickets are left it gives the impression that the tickets are popular, and thus it is more appealing to the customer. This has been shown by Hanson and Putler (1996) who found that by increasing the number of downloads reported by online software, further downloads were more likely, and participants rated the more popular software as more appealing.
The combination of these two techniques leads to people impulse buying expensive goods that they would normally debate over.
Hanson, W. A., & Putler, D. S. (1996). Hits and misses: Herd behavior and online product popularity. Marketing letters, 7(4), 297-305.
Petty, R. E., & Cacioppo, J. T. (1986). Communication and Persuasion: Central and Peripheral Routes to Attitude Change. New York: Springer-Verlag.