The answer here is sort of complex. I think most people's bottom line is
that they would like to meet someone to develop a serious relationship,
myself included. Sometimes when we state that in our profile, we run the
risk of missing out on the more casual daters ~ which is how it should
start, anyway.
The best way to develop a relationship is to have some casual dates and
see how your personalities match ~ give it time to get to know someone's
moods, likes and dislikes, dating style. Too often these dates boil down
to how attracted you are (physically) the first time you meet, and it
doesn't give either person a fair chance of taking it to the next level
as you would were you to meet someone "in real life." Ideally, you might
meet someone at work, at church, at a theatre project, the gym, through
friends, and, because it's not automatically a dating situation, it can
take several meetings for you to discover that you like they way they
look more and more all the time, their sense of humor, how they carry
themselves, etc. ~ and then you realize you are interested in a possible
relationship with them. On a dating site, everyone is looking for
instant chemistry (translate: instant sexual desire) and that rarely
happens.
So some of us may say we want a serious relationship but still respond
to someone who is looking for casual dating, because after all, that is
how it should begin anyway. And maybe we respond to someone who seems a
bit promiscuous because, hey! at least we know the person isn't a prude
and may not judge us so quickly because she wants to have some fun.
I have tried these sites off and on for years ~ and none of the major
relationships I've had were through any of them. But it's hard to meet
people, so we keep trying, right?