how do ratings work ?

people often ask me why i don`t yelp. 
to me, i enjoy food and i enjoy photos. together, my eyes can taste the food rather than read personal descriptions. 

of course not all food that looks good, tastes good.. so my rating scores are as follows:

 - don`t try
 - it was worth a try
 - definitely, a must try or "top of the crop" status !