The main function of data visualization, is to better understand the general concept of a data set quickly. Sure, if done effectively, data visualization can look organic and beautiful, but the primary goal always stands: allow the viewer to get the gist of the data quicker than looking at the sum of its parts. Rating systems are a great example of where we could do better, as Goodfil.ms has mentioned in their post about rating systems; 5-star rating systems are broken.