The 8-Node Analysis is used to get a better idea of a game. It helps to tell you some of its characteristics and certain aspects of it. For example, if you want to play a game that takes a while to beat you could use this to see how many playable hours it has and if it has DLC on top of that then that's an added bonus. If you are interested then to check out the story you could just watch the trailer for it and see if it peaks your interest. If there was anything else you wanted to know you could just follow the analysis.