Dating is different when you get older. You're not as trusting, or as eager to get back out there and expose yourself to someone.
When you hold me in your arms, are you the type of person that will make me feel safe and warm? Have you made it all the way to the end of my profile? Then what are you waiting for? Drop me a line and let's plan our next adventure!
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.