Who_Am_I wrote:
The terrible social skills.
^ this.
Put yourself in the shoes of the woman/man you're holding a first conversation with.
The other person has expectations of how a 'normal' person would chat and also of how someone who they would be attracted to would chat. This includes voice tone, topic flow, eloquence, body language and looks (lets just ignore looks for the moment..assume you are exactly the kind of person they consider physically attractive to get this variable out of the way).
It becomes fairly evident to this person in a matter of minutes that there is something 'off' or 'wrong' about you. They can't really tell what it is because its not like you're mumbling or stammering or behaving like any of the guys from the BigBangTheory. To this person that -thing- whatever it is, kills the first impression... the 'hey I like this person Id love to spend time with them' ,etc behavior that normally indicates a social connection/bond is forming. Unfortunately, if this person happens to be in the mindset of spending time with you a bit more just to make sure they didn't get a wrong first impression.... the second or third or fourth 'chance' they give you merely reinforces the 'something is off' feeling....and the end result is them not minding having you as a friend (usually a distant one) but not anything further.