Google AdWords is not cheap, however, if you can get more clicks & a higher click through rate, your cost per click will drop. 1 of the most powerful ways to get more clicks in a shorter time is simply to add urgency to your pay per click ads.
If you are selling products, you can limit the quantity, these are the words which you can use...
For almost anything that you are selling, you can give a time limit, these are the words which you can use.....
Many people actually failed while trying to use scarcity tactics because nobody believes them! Whenever you want to use such tactics, give people a real & reason why they must act now. When your reason is good, you will see your response rates shoot through the roof.
By now, you probably realized that urgency is created by scarcity. Based on some studies, scarcity is 1 of the most powerful factors that influence people to take action immediately. This is powerful, do not abuse it!