It'd be great if every women could take something huge. I've known a couple of women whose pelvic canal is so narrow they've had to have cesarians when they've had their kids. Four fingers to the second knuckle was a struggle with both of them.
I really shouldn't be disappointed on the very rare occasion I get a couple of fingers in a lass for the first time, and I definitely shouldn't add "for your age" when I say, "Wow, you're tight".