If you're a heterosexual couple, the problem could just be that what arouses men is often very different from what arouses women. A man may respond more quickly, whereas a woman's arousal may be more like "warm water that slowly is brought to a boil," says Joy Davidson, PhD, a New York City–based psychologist who's on the board of directors of the American Association of Sexuality Educators, Counselors and Therapists. "You might conclude that his libido is higher than hers," Davidson says. "It's not the case. They are processing stimulation differently and responding to different cues."
There also may be a difference in priorities, says Davidson: "If one person thinks having a passionate sexual relationship is critical, absolutely central to the marriage, and the other sees it as the icing on the cake, that is not a libido difference, it's a difference in values."
Someone with little prior sexual experience may simply not know yet what will turn him or her on. Your relationship is just the place to experiment with this mystery. Exploring it carefully and sensitively is generally good for both partners.