Are we talking about providers or women in general?
I'll direct my comments toward providers...
Believe it or not, I don't cum about 95% of the time when I'm with a provider. I'm also not one to "bang away" for eternity either. I used to make HER having orgasms a priority to the point of being detrimental to the session.
I can't *expect* every provider I'm with to have orgasms because the nature of the arrangement doesn't necessarily lend itself to things like her being orgasmic to happen.
The guys who seek out providers hand pick the ladies they want to see and can be as picky as they can afford to be, to a degree, and the ladies don't necessarily have that same ability. I know I wouldn't have seen most of the ladies I have if they could be as picky as I have been. As a result, I can't expect them to be as "wrapped up" in me as I would probably be in them for various reasons (our being together being a business transaction, physical attraction issues, etc).
So, I've stopped "worrying" so much about her having multiple O's and focus more on enjoying my time with her and going with the flow of our time together. When the issue of my not cumming comes up, I assure her that my not cumming is NOT related to her at all and try to put her mind at ease. I'm more into the feeling of the penetration and having the opportunity to worship her female form than the climax itself.
If I sense she's tiring of the sex, I will stop and suggest we do something else depending on how much time is left. When I'm with a provider, her comfort is a priority to me. If she's comfortable, she will hopefully be more open to me worshipping her and her body and that can lead to the best time for both of us. 
Peace...
there are so many variables. We just need to work together. Considerate communication helps.
As for myself, if the mood is right, and the sensations of touch and feel are good, whether it is BJ or FS, I might be done real fast, like one or two minutes if I just allow it. I've generally felt that is too soon, held back, and asked to go slower. Once I get over that initial urge, I can go and go and go. But sometimes that's not good either.
Sometimes the reason I last longer is that the sensitivity disappears, either on my part, or the lady is stretched a bit more and doesn't create the same sensations. And like jockeypants mentioned on the other thread, I can't say "abracadabra" and just cum on demand. Sometimes I will cum just fine. There have been times when I simply haven't cum. Not cumming doesn't mean I didn't have fun - I've had tons of fun without cumming! (Probably the ladies can relate to that, too) But yes, I would rather include cumming.
The thing I wonder is, should I let that first pop go fast, relax, chat, DATY and stuff and plan for a second pop? Or is it better to just make it one long session? I'm gathering from the other thread, that in many cases providers would rather have two pops with a break between sessions.*
But my days are not all alike. Some days I could cum twice (or three times) in quick succession, other days after one pop, I'm done. And so that leaves me wondering which way to plan because I can't particularly know which kind of day it will be.
Like I mentioned earlier, there are a lot of variables and I think considerate communication smooths the way. It doesn't offend me if a provider says that she's tiring, or feels too dry (which I may not always detect since I'm wearing a condom) and she would like a little break. Everything about a nice lady is good, whether it is just lying together and chatting or whatever. (I enjoy kissing, but not all providers want that.)
So ladies, if I go a bit longer for you sometime, don't get exasperated, just ask for a break. It's just great to be in your presence anyway! 
* Certainly for the fine ladies we usually see, I'm considering multiple pops in the alloted time as the norm. I'm not considering it the norm what I experienced with a rip-off. She got me off in five minutes and despite my paying for two hours, got up and left. Naturally that was one time I wished I'd lasted a long time!