Add reviews and ratings for better Google Search results

Reviews or testimonials are mostly said to work on the basis of social proof. Social proof is a psychological process in which people copy the behavior of others, in an attempt to reflect correct behavior. A testimonial tells you that someone you can identify with has bought a product and loved it. That must mean the product is just the right thing for you as well. However, ratings and reviews are not just valuable for your customers alone: Google uses them in various ways too, as I’ll explain in this post. Moreover, I’ll show how you can help Google show ratings and reviews in the search results, with the right Schema.org markup.
Ratings
Ratings for your website or online shop can be twofold:
For your entire business
For a specific product
Business ratings
Ratings for your brand or shop will most probably be given on a website like Resellerratings.com or Google My Business. Google will see these ratings and will even add Google My Business ratings to their Knowledge Graph information. The time that Google added stars to search result pages for any website that added these ratings in schema.org is over. Google was simply flooded with ratings, and it made less sense to add
Source: https://managewp.org/articles/13815/add-reviews-and-ratings-for-better-google-search-results

source https://williechiu40.wordpress.com/2016/11/10/add-reviews-and-ratings-for-better-google-search-results/