8 x 6 becomes the goal once 7.5 x 5.5 is reached. I think some men set their goals low in the beginning so they can reach them with more ease and from there they start to add to the goal. 8 x 6 is a number that begins the size of a monster and I think most men would agree that is where they want to be. But, with any measurement, once it is reached men will want more. So you will see someone start shooting for 9" after they reach 8".