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It should be simple. If the two people in a committed couple differ about how to spend leisure time, they could each spend some in their own preferred way, and some together. If the two people have wildly differing food tastes, some accommodation can be made so that they can eat together, one on organic veggies, and one on roast beef. If, however, two people in a monogamous relationship are not in agreement on sexual matters—when to have it, where to have it, or how to have it—there is rarely a satisfactory compromise.
At its simplest, if one person prefers sex at night and the other sex in the morning, sex at noon will satisfy neither. And it is rarely that basic or simple.
Take the extreme situation of a person who can only be satisfied by a dominance/submission ritual complete with various accouterments and costumes at least twice a week, while the other wants brief sexual intercourse with no preamble or decorative trimmings, maybe every few weeks or so. A vanilla quickie about every 10 days wouldn't begin to satisfy person A, while person B would find the original scenario an enormous chore, if not outright uncomfortable excess. Somehow, these two people want to make a life together with loving satisfaction for both.
The apparently obvious solution (at least to me) is that these two enjoy everything that they do enjoy together within their relationship, and go elsewhere to find a like-minded individual with whom to have sex. Sadly, this is not a solution that works for many, if any. Life would be much simpler if it did.
Over the years, I have seen variations on this theme of desire discrepancy in my counseling office many times. My simple solution of "have what you want elsewhere" and stop trying to make a round peg fit into a square hole, so to speak, is countered by the couple's own customary solution of having the other partner modify his or her desires: "If you only wanted what I want, there would be no problem."
Usually, the couple does work out some arrangement, more often grudgingly rather than gracefully, and peace is restored for a while until one person's mindset of being deprived or the other person's feelings of being pressured erupt again or takes their toll on other aspects of the relationship.
I do want to point out that this is not always a man versus woman, Mars/Venus disparity. It often occurs in same-sex couples as well. It's not only a high versus low libido struggle, nor just a liking for kink in opposition to very restricted sexual boundaries. A preference for a certain amount of sex at certain times and in particular ways can be modified by an act of will—sometimes. Sometimes nature will take care of the disparity, and the natural differences will not loom as large.
Very often, some of the needs that a sexual encounter between a loving couple fulfills can be parceled out. A greater need for touch in one partner, for example, can be assuaged through interaction with their children, social dancing, massages, and an affectionate pet. A desire for personal validation can be obtained through work or volunteer efforts. One's partner does not have to satisfy all the person's emotional needs, nor does sex have to carry the total burden of their expression. It's just not customary for a person who feels "my partner won't satisfy me" to look for alternate means of satisfaction and still remain monogamous.
I have no solution to the dilemma of desire disparity. I don't believe an ideal one exists. I do urge couples to carefully examine the needs of each and problem-solve together honestly and caringly for the greater good of both. Happy couples with disparities of all sorts—in height, age, income, temperament—often do manage to live together and thrive. This particular difference is just not an easy one to solve.
