The irony is that the opposite is true: available people are the ones who are dangerous, because they confront us with the possibility of real intimacy. They might actually hang around long enough to get to know us. They could melt our defenses, not through violence but through love. This is what the ego doesn't want us to see. Available people are frightening. They threaten the ego's citadel. The reason we're not attracted to them is because we're not available ourselves.