Relationships in general make people a bit nervous. It's about trust. Do I trust you enough to go there?
An ambitious go-getter. I'm attracted to people who set big goals and put all their effort into pursuing them. Even if your life's dream is to become the world's greatest thumb-wrestler, I totally dig it.
Nothing defines humans better than their willingness to do irrational things in the pursuit of phenomenally unlikely payoffs. This is the principle behind lotteries, dating, and religion.