The whole versus the sum of some of the parts: Toward resolving the apparent controversy of clitoral versus vaginal orgasms.
Maybe some of them also are secret hooker, who work at their private appartment and do it for pocket money? Some flush or sweat after an orgasm, but others do not.
Controlling the speed and depth of the action means you can go faster or slower or deeper depending on what your body wants.
Since there was no evolutionary need to eliminate the female orgasm, it persisted even when it was no longer necessary for fertility.
But this type of sex does come with that are important to consider before you try it.
But while clitoral orgasms may be the most accessible kind, this tiny, mostly hidden bliss button is highly individualistic.