Reason: In the default Revit tempate almost every category is unnecessarily turned on in all views so the same family shows up everywhere.
Solution: Create Additive Views instead of Subtractive Views for family categories that are only used in one or two views. By that I mean, start with most family categories turned off in your new view's visibility/graphics and gradually add the categories that you want to see.
Extra Tip: If you want future new views to be additive by default, create a view template. Then, when you apply the template to a view, check the option that reads "Apply automatically to new views of the same type."
