We like to see each others eyes so we can get a handle on what they are really thinking and feeling, however revealing ourselves can make us feel very vulnerable. We avoid eye contact when we don't want people to take a closer look at us. There are several reasons for this.
One of the most common reasons is we feel insecure. Eye contact invites more interaction, requiring our engaging attention. This can be intimidating with someone we feel less powerful next to. People with higher-status will tend to make more eye contact, while people who suffer from depression are less likely to make eye contact.
Another common reason is we don't want others to know our true feelings. We might feel our reaction will be unfavorably accepted. Anger, fear, and surprise are the hardest emotions to hide through our eyes. They are also the emotions we want to hide most. People who speak sarcastically often avoid eye contact while doing so, for sarcasm is a defense mechanism used by those who are too insecure to show their aggression or state their opinion directly.
If you are telling a white lie, you may hesitate to look someone in the eye because your eyes may give away the truth.
Emotional stability has also been proven to be perceived higher in those who make eye contact.
All of the above reasons for avoiding eye contact, the common denominator is the fear of rejection. Eye contact can act as a regulator for opening and closing the door to connection. The more eye contact you make, the more you are willing to put yourself out there, to risk rejection, and put your confidence into action. It becomes a catch 22, for the more you make eye contact, the more confidence you are creating.