Relationships in general make people a bit nervous. It's about trust. Do I trust you enough to go there?
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.
Hkum1976 has not specified any interests yet. Why not get in touch with them to find out what interests they have?