For me, there are exactly 4 reasons.
- I find you really, really attractive. So attractive that you make me nervous. I can’t even look at you because making eye contact with you makes my heart race. I am intimidated.
- I think you’re the most annoying person alive. So annoying that I’m trying at all costs to not give you a reason to talk to me. I will avoid eye contact and maintain a distance at all costs.
- I am super embarrassed. You saw me do something that I am mortified about or you embarrassed me somehow. Now I can’t look at you because of my shame.
- I’ve been given reason to believe you don’t like me so I’m trying to avoid awkward eye contact and keep a healthy distance. I might think you’re cooler than me so I assume you don’t want to talk to me and I’m scared of talking to you first.