What does it mean when I say hi to a girl and she says hi back but she avoids looking at me?

[Anonymous]

Could it be she doesn't really like me?

[Rania05]

Either she doesn't care about looking at someone's face when greeting them or was discarded by something else.
And yeah... She may not like you but also not dislike you, just plain indifferent

[mermaidcancermoon]

doesn't like you, or she's focused on other things.

[In_Trance]

could be