This experiment adds a number under a Call To Action (CTA) button indicating how many other people have already clicked it in order to: Sign Up, Order, etc. This number increases based on your average growth.
Social proof is a tremendous motivator. The longer the line at a restaurant, the more you want to eat there. This experiment allows you to specify how many signups you've received thus far to encourage people to take action
This also shows your visitors that there is demand for the product/service that you are offering
Let’s take this scenario: Seller A is selling almost identical kitchen gadget as Seller B. However, Seller A has 841 reviews, but Seller B only has 127 reviews. Most people will automatically assume that the product with more reviews is more popular and most likely purchase from Seller A.
The idea behind this scenario is that most people trust when they see others making the same choice. So when a visitor sees that many people have signed up to their mailing list, they will want to as well.
Ensure that the number under your CTA button is reasonably high. For example, showing that only 6 people have subscribed your Email List may have a negative impact. In this case, this experiment may not be recommended.