Just think about it - next time you sit at dinner or something, just think about what people say and how they get or want attention. This is especially evident with two people who like (or 'have crushes on') each other. And if you critically analyze the things that you do instinctively - those which you "just do" without thinking - you will see how your instincts are governed by insecurities.
This is my opinion, but I think it's quite intriguing.
