Use Loss Aversion
At the most basic level, there are two main drivers of human behaviour – avoiding pain and experiencing pleasure. These are key to every action we take. When people are faced with either limited availability, or a limited opportunity to get the best deal, they are more likely to buy. This is why buyers tend to act quickly when they are told that a product or special offer won’t last long.
In fact, studies conducted by Amos Tversky and Daniel Kahneman in 1992 have shown that buyers are more likely to act based upon loss (avoiding pain) than benefit (gaining pleasure) because gains are fleeting while losses linger.
In the below example from Boden, they’re leveraging the loss aversion factor by limiting the offer to 3 days only and then reinforcing it by applying an animated countdown clock to their email. Very effective and they work a treat.