There has been an ongoing and long-lasting collective aberration among students, making numerous and sometimes futile attempts to master English, about the “superiority” of English native speakers in the role of the language teacher. This prejudice is quite persistent, to the point that
there are a number of language schools that employ English teachers whose mother tongue is not English, delivering mostly grammar instruction, and English native speakers teaching communication courses. You can find some educational websites where you see the hourly rate for native speakers’ services exceeding the one of their non-native speaking counterparts.
On the one hand, there are non-native speaking teaching professionals, who learned the language by the book, were educated in their own country and lack the knowledge of the live English, you acquire by living in the country it is spoken over a significant amount of time. Grammar, however, was an integral part of their education and they are qualified to teach it no matter how their pronunciation and speaking skills may not be up to par comparing to their native-speaking colleagues.
On the other hand, there are a lot of eager representatives of the English-speaking countries, who learned their first language intuitively in the childhood, were not taught grammar at school, which is commonplace, and thus unable to explain and teach it. Following a one-month training course, and one month is all that is required, they are awarded with CELTA, Certificate in Teaching English to Speakers of Other Languages. They are quite enthusiastic to start enlightening their students because they do speak the language. However, just think about it, would you be able to teach your first language to locals after a one-month crash course? Isn’t this “gold standard teaching qualification”, as CELTA is known, a little bit substandard for an intelligent and demanding student? Not to mention the different dialects the native speakers are representing. I bet, depending on your needs, you prefer to be exposed to the literary kind of English, which is British Received or Standard American pronunciation, not to some geographically exclusive local dialect.
To make the long story short the students are offered the services of the two kinds of dysfunctional “teachers”, the former cannot speak properly, the latter is not a real teacher, but just an enthusiastic amateur.
To sum up, if you want to succeed in mastering English, look for a professionally-trained teacher with a solid linguistic background, who is capable of teaching the full spectrum of this multifaceted language, And if this teacher speaks your language, consider it a bonus, since sharing the mother tongue allows a teacher an additional insight into the mental process ongoing in the heads of the students of this particular language group. Your first language is a matrix existing in your mind and understanding of this matrix by a qualified teacher saves you a lot of time and effort in your journey to English proficiency.