I have dated several women who can't come to varying degrees.
1. A lawyer, not bad looking, not great, raised in a very uptight anglican family where the girls were taught never to put out and to keep a dime between their knees at all times.
Never came ever.
Never masturbated.
Lost her virginity very late, in her 30's.
Suddenly in her mid to late 30's she decides that she wants to do a 180 and start sucking and fucking. Except she really doesn't have a clue how. She was even seeing a therapist about her sexuality to her credit who was encouraging her to get out there and take her panties off a bit more.
I took it as a challange, to be the one who rocked her world, after all all the other guys she had been with (but a few) were probably inept in the bedroom.
I tried every trick in the book. And I mean everything.
No luck, no how. She wasn't even sure if she was coming or not. What finally stopped me from bothering her was the last time we were together in bed (true fucking story), I was doing everything in my power to make her come by going down on her. After about 15 minutes of tongue work which would have resulted in most women coming at least twice, she pipes up, "Oh I have to change my voice mail at work. She reaches over grabs the phone and calls her work to record a new outgoing voice mail message detailing her lack of presence at work and when she will be back, etc. (She was obsessed with OGVM messages.)
Anyway, I gave up. I was breaking my neck (literally) going down her and she was thinking about her outgoing voice mail message.
True Strory.
I never called her again, never returned her calls.
2. A nurse. At the time, she was 37, now she's probably about 41. Very nice looking woman. Tall, blonde germananic girl.
Likes sex, but never comes with a man. EVER.
Doesn't matter what you do - oral, fingers, clit massage, intercourse hard or soft or whatever position, toys, toys with oral.
She never cums.
Now for the funny part.
Once all the groaning and moaning was over, I would hold her tight (her instructuctions), bite her nipples moderately hard and she would one finger herself to a silent but shuddering orgasm within 60 seconds.
?????
Then there was that British nurse that I met who would come 50 times during one session. She even would come sucking my cock.
Now, that's a reverse problem if you are like me and get off on bringing a woman off. If you are with a woman who is no challange to maker her come, it detracts from it as well (though not nearly as much as those who don't come.)