I concluded that having read a product review, people felt more informed to make a purchasing decision. As a result, if they did click a link after reading the review they were more likely to buy the product. Those clicking on the top link seemed to be more in a ‘surfing’ mode. They clicked on the link less because they wanted to buy it but more out of interest to learn more. Some bought the product and some bought other products once they were ‘in the door’ at Amazon.
Once you’ve set up your account, do note that Amazon requires you to use product links and generate income from at least three of them within 180 days. If you fail to do so within that time, they will close your account. If you are able to satisfy that requirement, Amazon will review your account as well as your usage of affiliate links once the first sale is complete.