Why do girls ignore messages from a guy?

Don't they know how much it pisses us off? I know there could be a hundred reasons that a girl might not respond to a message but doesn't change the fact that it pisses me off to the point that I want to kick someone's ass. If a guy is nice and polite, there is no reason you should ignore him. If you said hi to someone on the street and they ignored you like you don't exist, you would be mad too. No, girls aren't required to talk to you but they shouldn't assume that you're interested in them or want to go out with them just because you sent them a message. Nor should they assume you're a douchebag because they received messages from douchebags in the past. If they don't have enough time, they should modify their profile so they don't receive so many messages instead of being an attention whore. So in your opinion, what is the most common reason they ignore messages?
They assume you are interested in them and don't want you to think they are interested in you.
They automatically assume you're a douchebag because douchebags messaged them in the past.
Women by nature think they are better than men, therefore feel no need to reply.
Good looking girls get too many messages and don't have enough time to reply to them all.
They're too shy or scared to reply back.
Select gender and age to cast your vote:
Why do girls ignore messages from a guy?
Post Opinion