If we lived in an 8 inch girth world, tampon companies would have to retool...
Having 6 in + girth experience, each 1/16 in (for example) more the vagina has to stretch beyond it's comfortable capacity makes it more and more difficult. Granted every girl is different, but if a girl can just stretch to 5.5 at the start of pain, than 5.75 may be very painful at first. Now imagine every 1/4 inch more than that. Big and huge to a woman may not have to be that far apart on the measuring tape which is why us guys scratch our heads wondering what these women are talking about.