All products have a star rating directly under their product name. I just noticed that when I click on any of my Glass Coasters, a star rating does not appear. Here is an example:
https://www.zazzle.com/pink_collarette_dahlia_floral_glass_coaster-256186535139883020
And here is an example of a product that does has a star rating:
https://www.zazzle.com/white_daisy_on_black_floral_coaster_set-256637109606461675
I believe you are referring to the star rating of the MANUFACTURER (not the product type). The examples given are two different manufacturers.
The “star rating” is a conglomerate of review ratings. If you scroll down the product page and click “other designs” under the Review section, you’ll see all the reviews for that product and its score. In your example the acrylic coaster sets have had 40 reviews equaling 4.9 stars overall.
The glass coasters though, noone’s happened to review them yet so there is no star rating to show. 
I understand that. What I am saying is that all of the glass coasters are not showing the row of stars underneath their product titles. I believe this is some sort of glitch because all other products in the store do show a row of stars underneath their product titles. I hope I am making this a bit clearer.
I think I may have confused everyone. I need to clarify that the star rating that I am referring to is found when I click on a product in the back end of my store. I am not referring to the manufacturer star rating at the bottom of the page, but at the top of the page, right underneath the product name. It is not the same. I am very confused as to what the numbers mean. There is a number next to the stars and also a number in parenthesis. What do these numbers mean? Is this something that will help me out as a designer in evaluating my product? And as I said before, all products have this, except for the glass coasters. Actually, I found 2 other products that fail to show this particular star rating underneath their product name: Case-Mate iPhone cases and Mini Clipboards. I am wondering why these products do not show this info beneath their product names like all the other products do. Again…I am referring to products found in the back end of my store. Thank you for your patience for helping me to understand this product rating and why it is not found on some items.
I do not see any other star ratings, other than the PRODUCT MAKER, or in the PRODUCT REVIEWS.
Please post a screen shot of where you are seeing something different.
What you see directly underneath the product title is the same as what you see when you scroll down the page and click “other designs” in order to see all the reviews. It’s just showing the average rating that product has received from all its reviews. In the example of the acrylic coaster sets, you see “4.9 (40)”. This means out of 40 reviews, it has earned an average of 4.9 stars. Glass coasters and mini-clipboards don’t have any reviews from customers yet so there is nothing to show.
