One of my high school teachers once corrected me. He told me something, and i heard it differently. He basically said "you heard what you wanted to hear, not what i had to say." He was correct. And made an excellent point, i'm grateful to him for this amongst other things he taught me.
I've been thinking about it lately:
A) Talking is usually done for one of two reasons.
1) For the speaker to communicate that which he wants.
2) For the speaker to give the listener what he wants.
B) Listening is quite similar with its reasons.
1) To hear that which he wants to hear.
2) To listen to what the other person has to say.
Reading and writing are no different.
A few things can be said about this. Cases 1 are being subjective, whereas cases 2 are objective.
When talking, speaking objectively is usually the best way. To think about the other person, not to waste their time, and to communicate more efficiently. However, subjective talking has its place when talking about subjective things, such as one's feelings, ideas, and the like.
Listening, however, should almost always be objective. Otherwise, why is the other person talking? When being truly subjective in listening, we even hear what was not said. This has a scale. The more we expect or want something to be said, the further it can be from what the other person is actually saying.
This isn't even uncommon. A asks B a riddle to stump B. B asks a question before providing an answer. A hears B's question as an attempted answer and jumps on him to tell him the real answer. A's excitement caused subjective listening, ultimately not to hear what B actually said.
I think we all do a bit a both, like a sliding scale, and the goal is to do our best to be objective. It's hard though. Though, i think talking objectively is harder than listening objectively. It's not just information we give over, but a little bit of ourselves.