I find much of the discussion about what makes a good teacher or what is needed to do the job well mostly ignores the student’s perspective.
I suspect most teachers have spent a little time in the classroom attempting to learn a foreign language, but often we fail to reflect or utilize our experiences.
While there are many types of “English teacher” and exam prep and preparation for passing specific tests might require specialized skills and knowledge, there are no magical ways to actually “learn” a foreign language. Obviously some techniques work for some learning styles while others work better, but no foreign language teacher is going to have any special insight into the language which is both useful and unknown to most native speakers.
I have seen research suggesting it takes about 10,000 hours of study and practice to become fluent in a language (including our native one). Another study suggest it generally takes about 7 years of intense study to become fluent in a second language.
Looking at my own experience in learning foreign languages, I see most of the advice given to new teacher on this site conflicts with my own experiences. Although my studies have occurred as an adult which might be different from the perspective of younger students.
I can’t say there is any one style of teacher I prefer, of course there is nothing wrong with having some fun in the classroom, but generally I like a teacher who can provide structure, explanations, useful examples and some gentle corrections of my errors.
But there are two types of teacher I have had which deter my learning.
The first is the babbler. Once you get to the upper immediate of advanced levels schools tend ban the use of English in the class and students are expected to only speak in the language beginning learned. Fair enough, but there are times when 10 minutes of explanation, examples and confusion could be avoided by a 10 second translation. But also some teachers babble on just like they were speaking to another native speaker. Hey, if I knew every word in the language I was learning I wouldn’t need to be taking a class. Slow down and choose your vocabulary carefully.
The second is the type of language teacher who abuses their position as head of the classroom to expound on their own personal philosophical, religious, cultural or political views. I consider myself a highly educated person with a wide range of knowledge, generally far more than my language teachers. I really don’t want to spend my time listening to half-baked ideas, stereotypes and misinformation, I am there to learn the language. If I want to understand philosophy, I will take a class taught by someone who is an expert in the subject.
I prefer a language teacher who creates structure and provides guidance in learning the language, mixes explanation in both the native and target language and sticks to the topic they know.
But maybe I am a usual type of student. So I don’t necessarily follow the idea of speaking only English in the English learning classroom or as a language teacher try to impose one’s own specific values and world view upon the students. A love of languages and a desire for life-long learning, ok, but don’t abuse one’s position as a teacher to advocate one’s own specific values.