Superficial
We live in a populated world now-a-days, close to 7-billion people around the world, the chances are quiet low for us to find the one; about 0.000000014% to be exact. I don't personally believe in the one, but one thing I do believe in is that if you really want to, you can build a relationship, so strong in nature, that you will refer to your partner as the one.
We have all these criteria in our minds, these lists of specifications for people's personalities, behavior, their choice of friends, their choice in clothing and style, the kind of books they read, the kind of music they listen to, the dialect or accent they have, and how big/small their breasts/muscles are, what color their eyes are, how good of a kisser they are, and many other things.
We use these requirements to "protect" ourselves: we meet someone new, we talk to them for a few minutes and if they score well on our list then we keep interacting with them, otherwise – they're out of the picture.
If you think about it, all we're doing is restricting ourselves from meeting new and interesting people. Someone who you would be able to connect to in ways you would have never thought of. If only we took the time to get to know every person we meet...
From the point that you meet someone–the first contact–until the moment you truly know who that person is, what their past is and how those certain experiences they've had in their past affected them, for them to become who they are now, exists nothing but uncertainty–could they be someone you could really connect to? Emotionally, spiritually, sexually?