CodeCanyon - Product Countdown v3.5.2 - WordPress Plugin | 521 KB
With a countdown displaying on your products you create something like a scarcity mentality in people. It can create a feeling of fear, anxiety and maybe desperation just because they see that the price will rise in a specific period. It also make someone think that s/he has got only one shot right now. Buying a product then relieves much of the pressure (and the feeling of fear).