Some developers wanted to get a higher rating and they will offer a good review on their project in exchange of the right amount of money. Its business all of those review sites wants to attract money on their pocket and makes a bias or false rating to impress the investors that the project is good. ICOs rating nowadays are not reliable and not a good tools to be a basis in finding a good project as those reviews are bias and scripted. Smart investors don't rely on those ratings; they will find it in the words from the developer from their exposure on various crypto events.