People have habitual modes of communication- ways that they try to get stuff from their heads into yours. There are lots of levels of magnification you can look at this, everything from NLP's modalities to how much a person relies on logic or emotion to make a point.
The habitual modes are a huge piece of what we see (in others) or project (ourselves) as personality. If someone is loud, uses anger to attempt to invoke fear and tries to stand too close and at a higher elevation, he is read as a bully. Someone who talks about himself more than the issue at hand is read as arrogant. Someone who talks around the issue or is constantly distracted by other things is an airhead if otherwise charming and nice; manipulative or stupid if not.
Habits become habits because they worked, and communicating is something that we learn so young that it can be very difficult to change. Cute talking tends to work at two years old, less so at six or eight. But, if it does continue to work through six and eight because it is rewarded, it can become a habit into adulthood that doesn't work. People become bullies because they got away with it. They become passive victims because that mode protected them from the far more horrific things that they imagined might happen if they asserted themselves.
You have a teaching style, (even if you are not officially a teacher, you teach all the time.) If you have never received specific training or at least given it a lot of thought, your teaching method is probably heavily influenced by your normal communication mode. If you are a brash, arrogant jerk in your private life, you are probably one of those loud teachers constantly pointing out tiny errors and keeping your students constantly on the defensive.
Two side notes, here-
1) Sometimes this is not true at all. Sometimes when a person drops into teaching mode they have an entirely different personality, often cobbled together from TV shows or memories of good teachers. This is not always effective- a good dramatic presentation of teaching is not the same as good teaching. What makes good entertainment is not the same as what makes good education.
2) And some people, when they start to teach or put on a blackbelt and get in front of a class undergo a personality change because they finally have the confidence (really the self-perception of power/authority) to start acting in ways that they were afraid to do before. Almost always negative.
If you have one or a few communication strategies and can't change them, that amounts to a personality disorder. Think of and treat people as tools and toys, you're an Anti-social Personality Disorder. Other people only exist to acknowledge your greatness? Narcissistic Personality Disorder. You manipulate people through your own emotional upheaval? Histrionic Personality Disorder. You espouse the deeper truths of a reality not open to the common man (or just believe you've been abducted by UFOs)? Schizotypal Personality Disorder. On and on.
Most people have a few strategies. Logic. Connecting the idea to the physical world. Emotion. Big concepts or building the idea brick by brick. Metaphors. Metaphors presented as truths (a lot of the chi demonstrations I've seen, for an example).
Healthy people change strategies when they don't work for them (an inability to change is why they are called Personality Disorders). Emotion ("My parents are ill") didn't get me a raise, so let's try logic ("I've saved you 30% in Worker's Comp claims in the last four years.")
That's good, but it's reflexive. It still comes back to the person. This didn't work for me, so I'll change something. That hurt, so I won't do it again.
They are levels of maturity.
A Personality Disorder is locked into a behavior program that was solidified very young and won't change.
The average person changes strategies based on personal consequences.
A good teacher changes strategies based on what is working for the student. This is a huge step in maturity. The focus, for the first time, is outside of the communicator and monitoring the receiver. This is big and basic. The instant that you grasp that your attempts to communicate are about the receiver, not about you, your ability to communicate- to write and speak and, I don't know, interpretive dance- all jump to another level. Not automatically, it takes skill and practice, but the potential to improve jumps by an order of magnitude.
The next step, with experience, is to plan the communication with the student in mind and from the student's point of view from the very beginning. It is still about the student, but now trying to plan rather than getting steered by trial-and-error. You will make errors, though, so you have to keep monitoring. Otherwise, it is about you even when you are pretending it is about the student.