The misconception may come from the idea that all physical characteristics are somehow connected by a single underlying pattern. While hormones certainly influence many aspects of development, that does not mean that one visible body feature can be used to predict another person’s intimate anatomy.
For example, two women can have similar breast sizes while having very different vulvar anatomy. Likewise, women with very different breast sizes can have similar genital anatomy.
There is simply no reliable visual formula connecting the two.
Another important misconception is the idea that breast size reveals sexual experience.
