People never truely hear what others say to them. They hear the words that are spoken but they reinterpret them by injecting their own knowledge and experiences into what was said and creating an entirely new meaning tailored to what they themselves are most comfortable with. This interpetation is quite often, very different from what the other person actually said in the first place.
My favorite example of this is the question "Do you have a watch?" Their are only 2 possible answers to this question, yes or no. You either have one, or you don't.
Most people will instead assume you want to know what time it is and precede to either give you, or tell you where you can aquire, this information instead of the information you asked for. If you persist in trying to get the information you really want instead of what they decided you want, they will usually get irritated with you because you're contradicting their interpretation of your own question.
I've actually gone to the extreme of saying to someone "I'm going to ask you a multiple choice question, the choices are yes or no" before asking them the question and they will still give me a totally different answer based on their own reinterpretation of my words.
It's no wonder there is so much conflict in this world. People don't hear what other people say, only what they want to hear.