Why some women don't reach orgasm through intercourse?

Hello and welcome to EmpowHer,
I personally believe that many women do not orgasm because they do not know their bodies well enough.
When having sex, women often allow their partner to take control and except to orgasm.
But this is not necessarily going to work. Each woman must know the stimulation she needs to climax.
If she doesn't know, how can her partner know?
On a side note, the male point of stimulation is usually concentrated in the genital area. For example, men can usually reach climax even if the only body part stimulated in his penis. This is not often the case with women and that kind of sex hardly ever makes a women orgasm.
Women often need a lot of foreplay and stimulation in more places than just the genital area. So, in order words, since men require much less than women to climax, they sometimes do not give proper stimulation to their female partners in order for her to climax too.
So, take the initiation and show your partner what you want/need in order to orgasm.
Below i have pasted a link to a HER article that talks more about how sex works for women.
https://www.empowher.com/sex-amp-relationships/content/how-sex-works-women
Faith