Until they run across someone they think they can read, but then cannot. Responsible people recalibrate and adjust; others keep insisting that their (mis)interpretation is correct, however much it diverges from the actual meaning of the other person.
That is a source of a lot of trouble.
Example:
When I was a kid, people would comment that I looked angry when I wasn't. One day, the principal's husband came and spoke at a school assembly, and he misinterpreted my body language as "hostile". No one consulted with me about this, but my mother was called in to the principal's office to discuss it.
The principal and her husband had arrived at the notion that perhaps I was hostile toward men in general, and that maybe this meant I had been sexually abused by one.
The principal told my mother her concerns and strongly urged her to take me to a counselor. She did, and she left me alone with the counselor. The counselor wanted me to play with toys in a small sandbox, and while she kept me occupied with that, she asked me questions.
When she asked me if my father ever "touched me in a funny way" (or whatever similar phrasing she used), I knew exactly what she was asking, because I already knew about sex. I also was aware of Freud's idea of the Oedipal Complex. (My mother had explained sex to me, very straightforwardly, when I was about 5, and I knew about the idea of the Oedipal Complex from books that she would leave lying around.) I was embarrassed by the counselor's question, but I answered her frankly, and said, "No."
She let me continue playing with the sandbox toys, and she asked some questions that were probably "filler" questions. Then she got back to the point. Not 10 minutes after the first time, she asked me again, the same question.
At that point, I was terrified, because I had already answered and told her that he didn't. Why was she asking again? She must not have believed me when I'd said no. Most likely, she was just doing her due diligence, because kids sometimes deny having been molested when they have been, and she just wanted to make sure. But I didn't know that. I just thought she didn't believe me.
My father never did anything of that sort. But it briefly occurred to me to answer the counselor with a glib joke, and if I had answered with the line that I was thinking of, there could have been horrible results. Fortunately, I didn't, and I just answered "no" again. But I went away thinking that she was convinced that I'd been molested, and that she was going to tell as much to my mother and my teachers.
Just because some adult man who didn't even know me thought I was scowling at him.
---edit---
I'll clarify that I didn't know about molestation as such, or the likely consequences to my father if accused. I knew about the Oedipal Complex, and my horror wasn't at the thought that my father could be accused; it was at the idea that I would be thought, by my teachers and others, to be romantically attracted to my father. I was terrified of that reputation. That's why it was only lucky that I didn't implicate him by joking around with the counselor. I had no idea, at the time, of the way that would have affected an innocent man.