Yep, I always bring lube, may just be hormonal (certain times in a woman's cycle she is dry, certain times she is more able to naturally lubricate) but even with that said, I do find latex extremely drying and uncomfortable after a couple minutes.
Also if a guy is thicker or bigger, or is at "half mast," lube can help with that final push to get him inside me where it might otherwise be a losing battle.
I've certainly never correlated it with whether I am turned on or not, we women just cannot always control our cycle hormonally and when we are prone to get and stay wet depends a lot on the day and time in our cycle, and like I said, even on the wettest days, the latex of a condom is extremely drying in my experience (providing on and off since 07, sexually active since 03 or 04 or so).
I have also heard it can be more pleasurable for a man, to put a little lube *inside* the tip of the condom too, so sometimes if I remember I will do that, for his pleasure.
Just my two cents, but I will say that when using condoms with civvie partners in the past (don't really have time/energy for civvie dating ATM!) I have also considered lube part of the standard sex "kit" due to the condom issue, so it really has nothing to do with the guy or our attraction/chemistry.
Although I will say that if the guy makes absolutely no effort to arouse me, or hasn't showered, and I am genuinely turned off, then yes, time to lather up the lube, in much larger helpings than usual, to make intercourse feasible lol... it's not an issue, no paying client is required to provide foreplay for the woman if he doesn't get off on getting a woman off, though I find most clients prefer a mutual session, but for my own comfort, if I have absolutely no lubrication or blood flow and there has been no foreplay or intent to work ourselves towards arousal, then yes, lube is what allows penetration to occur with minimal discomfort. That said, that is a rare occurence. (And actually, chemistry/attraction aside, our bodies are made to respond- touchy subject, but for example, in the case of rape, a woman may self-lubricate- it's biology- it doesn't mean she wants to be raped, but there are many things about our sexual response (perhaps similar to mens' control or lack there-of in getting or maintaining an erection?) but it's not always conscious...
But yeah-- for the most part I find my sessions are about mutual pleasure, and I generally do get wet when a man makes an effort to reciprocate, depending on the time of month of course, and certain meds can also cause a woman to have trouble lubricating naturally even though mentally she may feel turned on, but yeah- I still prefer to add the additional silicone/water based lube as a matter of routine for the maximum wetness to last longer as the latex dries out...
HTH! Have fun and play safe!
*licks*
xoxo,
Marea