I don't understand the whole dating thing. I know right off the bat if I'm interested in someone, and I don't want them to waste their money on me and take me out to eat if I know I'm not interested in that person.
Intelligent, sweet, down-to-earth and adventurous. Bonus points if you're a little bit quirky.
People could rationally decide that prolonged relationships take up too much time and effort and that they'd much rather do other kinds of things. But most people are afraid of rejection.