There was a Dateline NBC television segment about low sex drive in marriage, that was also placed on the MSNBC web site, along with an explanation of a survey they introduced by saying: 

"Below, are common myths about “sexless marriages”  from Drs. David Schnarch and Ruth Morehouse, who have over 40 years of clinical experience and reviewing research on sex and marriage. As they explain below, less passionate marriages aren't necessarily because of the length of the marriage, the age of the people involved, or because of the presence of perceived physical problems."

    Myths about passion in the bedroom
    Sex doesn't have to die in marriage — and desire can be rekindled

My comments are in red; their material, in black: 

1. How often do you and your partner have sex (on average)? 
        Not in the last year 
        Several times a year 
        once or twice a month 
        once or twice a week 
        four or five times a week 

More than likely this question is meant to ask, and will be taken to mean, how often you and your partner have intercourse with each other.  But there can be sexually intimate times, in fact many of them, that do not have intercourse as their goal.  Snuggling in bed, or gentle petting and caressing on the sofa or with one's spouse in one's lap, massage or back scratching, shampooing the other person's hair, etc. can be pleasurable, intimate, sensuous and sexual ends in themselves,  not "fore"play to something else.  And that can happen between a couple many times a day every day, sometimes perhaps resulting in arousal that is taken further, but probably far more often not, and not intended to be, taken further.

    2. What are the longest periods you have gone without having sex together? 
        7 months to a year or more 
        3-6 months 
        1-2 months 
        2-3 weeks 
        A week 

What if it is none of the above (if people were actually in the same location the whole time; i.e., not counting long business trips or army overseas assignments, etc.)? Again, this seems to put a premium on intercourse, because otherwise some people may not have gone more than a day, if that long without touching one another in a sensuous and/or loving way.

    3. Just how passionate and erotic is your sexual relationship? 
        Sex is non-existent 
        Sex is passionless, mechanical, and non-erotic 
        Sex is friendly but predictable and uninspired, lacking in creativity and spontaneity 
        Sex is pretty steamy 
        If it got any hotter, our bed might catch fire 

The options available here for answers are insufficient and give, or reinforce, the misleading impression that if sex is not "passionate" or "steamy" or really "hot" that it is therefore passionless and dead; and that is simply not necessarily, or even likely, true.  There is at least a third option besides "passionate" and "mechanical".  "Passionate" in regard to sex (as opposed to in regards to interests) generally implies being (nearly) out of control and wanting to get right to it, ripping each others' clothes off, hot, steamy, gymnastic, acrobatic, animal monkey sex or something.  One option they are missing -- perhaps the most important option at least many times for many people -- is one involving love-making as being tender, gentle, perhaps sometimes playful, but primarily sensuously pleasurable, touching and playing that is stimulating and inspired but yet still deliberate, not wild or out of control -- and just trying to make it feel really good for as long as possible with someone you care about pleasing and being pleased by.

    4. How much intimacy and emotional connection is present when you have sex? 
        Sex is an intense meeting of our minds and souls, and not just our bodies. 
        Sex is a little personal, but much of “who I am sexually” never really shows. 
        Sex is mostly on trading orgasms. 
        There is no joining. I spend most of my time fantasizing about other partners, or thinking about other things. 
        Sex is non-existent 

These answers don't seem to me to cover my feelings or experiences.  Even with terrible sex, I wouldn't fantasize about being with someone else.  And as one of my male students said in class once, about a time when he had been in the middle of intercourse with some girl he then realized he didn't want to be having intercourse with, he was not fantasizing her into someone else nor was he thinking about something else.  He was thinking about what he was doing and wondering why in the world he was doing it or what he should be doing to relatively gracefully extricate himself from it.  As when women fake an orgasm to get the guy to leave them alone, they are thinking about the sex they are having, but they are not thinking positively about it.

I also believe that sex, as sex itself -- a physical activity-- apart from the "pillow talk" acompanying it, is never a meeting of minds and souls either, no matter how great the sex is.  That is something altogether different, and it does not come through sex if it comes at all.  Nor does "who I am" have to do with sex; sex is part of who I am, but not some deep display of the characteristics of myself most important or significant to me. That comes out more in conversation or writings or just in my own thoughts.  It may influence my actions and behaviors, but even when it does that, my actions and behaviors reflect only a small part of what is "me" in the sense they mean.

    5. Do you and your partner structure your relationship to avoid sex and intimacy? 
        We go to bed at the same time and use it as a time to connect including sexually. 
        We go to bed at the same time and connect, but it rarely leads to sex 
        We go to bed at the same time, but there is no physical or emotional connection between us. 
        We go to bed at different times to avoid having sex. 
        We sleep in different bedrooms or live apart much of the time. 

This just has to do with bedtime intimacy.  What about all the other kinds of intimacy that can occur when you sit or lie close, snuggling and watching tv together, perhaps one in the other's lap being caressing or being caressed, or how you talk to each other or "break bread" together.  There are many opportunities each day for touching and giving pleasure without thereby intending or leading to intercourse or other kind of orgasm or even to wild passion.

    6. How often do you and your partner kiss during sex? 
        We kiss multiple times in almost every sexual encounter 
        We kiss at least once in three quarters of our sexual encounters 
        We kiss at least once in half of our sexual encounters 
        We rarely kiss when we have sex 
        We never have sex 

What is kissing supposed to be a sign of?  Kissing is sometimes really good, but sometimes there are other things to do that are better.  Sometimes, for me for example, though I love kissing either without sex or during sex, after orgasm I really don't like kissing usually, even though I am feeling very loving.  Something about the way my mouth is dry afterward makes kissing just not feel good and seems sort of mechanical and gross, even though I might be very loving or excitedly happy or feeling very intimate.  And some people get so passionate during sex that they can't kiss.  Other people kiss when passionate.  I don't think just the frequency of kissing during sex necessarily determines the quality of the sex or the nature or intensity of the feelings that accompany sex.  One can feel very loving without feeling like kissing.  And, of course, many people can kiss without necessarily being very loving.

    7. Do you and your partner ever have eyes-open sex? 
        I and/or my partner sometimes have orgasms while looking into each others eyes. 
        We sometimes make eye-contact during sex. 
        We open our eyes, but never make eye-contact 
        One or both of us keep our eyes closed during sex. 
        We never have sex 

This also seems to me to have more to do with individual psychology and preference than with anything about the relationship.  Whether you close your eyes when you kiss or are touched in a way that feels great, or have intercourse or even while you are climaxing or not, seems to me to have nothing to do with anything.  Some people think that people that kiss with their eyes open are not into it, but one can be really into it with their eyes open while kissing, and enjoying seeing the beauty of the face they are kissing.  Obviously, if you are watching tv while kissing, that is a different matter probably.  As to eyes open orgasm, it depends, I think on its intensity in part, and on your physical position in relationship to what you are facing.  A really intense orgasm is difficult to keep your eyes open during, though it can be done.  Watching the other person's (face and body during their) orgasm is really cool.  But if you are facing down into the bed over their shoulder, normally you would close your eyes. Even if you are getting a back massage while lying face down on a bed or other surface, you would typically close your eyes.  Though if you were lying facing each other side by side while having your back stroked, you might be looking into each other's eyes or at each other's faces.   If you are on bottom looking up, you might be more inclined to watch your partner while you are climaxing so you can see them watch you while you are.  Or so that you can savor their beauty while you are climaxing.  That is cool.  But sometimes one's eyes just involuntarily shut with pleasure.  So I don't think open or shut eyes, by themselves, mean anything.  Could mean one is basking or that one is bored.

    8. Do you and/or your partner have sexual dysfunctions (problems with lubrication or erections, or orgasms)? 
        Neither of us have difficulty getting aroused or having orgasms. 
        I am (and/or my partner is) slow to arouse, but once we get started, we don’t have any difficulties. 
        One or both of us occasionally have difficulty with arousal and/or orgasms. 
        One or both of us frequently have difficulty with arousal and/or orgasms. 
        We never have sex 

This is far too much emphasis on "arousal" and orgasm, as opposed to great or sensuous or comforting pleasure of touching and intimacy.

    9. Do you or your partner struggle with low desire to have sex (before you start)? 
        Almost always 
        Usually 
        Sometimes 
        Rarely 
        Never 

Not being a struggle doesn't mean one needs to already have desire.  As long as one is not unwilling to participate, the rest will come just fine.  And if it doesn't, one can still please and pleasure one's partner real well at the times that might be appropriate.
 

    10. Do you or your partner have problems with lack of desire during sex? 
        Almost always 
        Usually 
        Sometimes 
        Rarely 
        Never 

Even for couples to whom that question would be funny because they are both almost always interested in one form or another, there are times of greater or lesser desire, though not of lesser enthusiasm for having it be good and also be intimate.  Sex does not have to arise from lust or horniness or sexual desire; it can arise from the desire to please one's partner or to be intimate.  Even men can have sex, can have erections that allow intercourse, without their being really all that much "in the mood" for sex; that is, without their becoming lustful or sexually aroused.  Lack of sexual "desire" is not necessarily either a deterrent or an obstacle  to great sex.

Once in a great while even good sex is not exactly intimate though,  if, for example, one's mind is on other things, which sometimes happens.  They may not diminish the physical pleasure of the experience but other stresses can sometimes make sex be less intimate in some ways.  This can range from business or family worries to having to be careful during pneumonia sex or arm-in-a-cast sex or being on some deadline to get back to work after lunch, or whatever.  Even sex during later term pregnancy for women who love and desire that, while being very pleasurable and loving is not always intimate because you both have to be physically careful about weight and forces and angles and movement, sometimes avoiding many typically intimate positions.  And great, passionate monkey sex is often itself not intimate.  Or a mutual "quickie" may be extremely intense and pleasurable and exciting without being intimate.

I want to make some final comments here about "exciting" sex.  Sexual excitement should not be confused with excitement that accompanies sex.  There are situations in which more than one kind of excitement occurs simultaneously, and sometimes people mistake one sort of thrill for another.  An example is the excitement or thrill of having sex in a place one is not supposed to, with a risk of being caught.  Empty law school classrooms seem to be a favorite (of law school students and their lovers), as do various outdoor or other public places, and passenger airliners (mile high club sex), and business offices, or at home with a lover's spouse gone. While that can be extremely exciting, it is not usually because the sex is particularly comfortable or physically all that good.  Often it is somewhat hurried and furtive, with most clothes being left on. Sometimes, as in some airplane bathrooms, it is cramped and uncomfortable.  So one should not confuse the pounding of one's heart from fear or logistical difficulty with the pounding of one's heart from sexual stimulation, desire, or excitement.  There may be both, or the sexual excitement, if it has been building previously, may even be greater than the environmentally induced excitement.  But the two are not the same thing.

Similarly, when one has won a championship or accomplished or completed some other task that is significant and exciting, and one also then has sex, there are two kinds of excitement operating at the same time, not just one.  I think this even operates in regard to initial sexual experiences, whether with a particular person or with one's first few lovers (if one has more than one lover in one's lifetime).  "First sex" is often exciting not only because it feels good or has high romantic or sexual excitement, but because it culminates perhaps a period of anticipation and because it is often frightening or nerve-wracking in many ways.  So there are many elements (e.g., from fear of embarrassing oneself or fear of being humiliated, fear of failure, fear of inadequacy, fear of consequences, fear of being caught, fear about whether one is doing the right thing, besides whether one is doing the thing right, to just the outright excitement of the apparently near fruition of a long time of anticipation, and the thrill of apparently being liked enough for someone to find you sexually attractive and desirable enough that they are willing to have sex with you) that accompany whatever sexual excitement or gratification or pleasure there might be (if any in those early times). What is important is to distinguish the extrinsic excitements from the sexual ones.

Often, it seems to me, when individuals or couples are seeking to rekindle that kind of sexual excitement they had at the beginning of their relationship, by going to romantic places or role playing or by having sex in a commercial airplane or some other risky public place, they are not really seeking to rekindle sexual excitement, but heart-pounding excitement with sex -- either from joy of the beauty of a nice place or the comforts of amenities (spas, golf, good food and service) or from fear or from the anticipation of first time (though in this case, fantasy or imagined first time) sexual fruition with a new person.  It is even entirely possible, it seems to me, that it was not the sex itself that they enjoyed early in their relationship but the extrinsic excitement that accompanied it.  I just think that people who enjoy intimacy and caressing and touching each other and who enjoy the stimulation of that touch when it leads to sexual arousal, are not likely ever to be looking for ways to make sex more exciting, because sex itself simply is exciting, particularly with someone you love or perhaps even like or care about. And couples who grow apart and out of love may not be able to attain sexual satisfaction with each other, not because they don't like sex, but because they don't any longer like (it with) each other.  And adding all the external excitement in the world in any of these cases is not going to make sex any better.  It is just going to, if anything, give them some sort of excitement in place of sexual excitement while they are having sex.  There are probably varying degrees of this, and I don't mean to oversimplify it here, because there are probably combined or synergistic excitements that are all part of the sexual experience to some extent or other, or in varying proportions, in different cases. But having bad sex or having sex with someone one doesn't like may even override all the external excitements to still make the sexual experience be lousy, just not as lousy as it would be without the external excitements.  Bad sex with good chocolate is possibly better than just bad sex by itself, even if neither experience is particularly desirable or good or worth having.

There are too many psychological and emotional nuances related to sex, or (potentially) accompanying sex, to reduce it to simply being either passionate or mechanical.  And those who feel that the only good sex is passionate and intense in the way seemingly meant here are probably doomed to failure and frustration, while at the same time missing out on all their relationship might have to offer sexually that could be wonderful for them.