We have pretty much all gone to school at one point or another and found both terrible teachers and inspiring ones. The impact from both was usually very high, whether in good or bad.
Let’s focus on the good times though. A good and inspiring teacher will naturally end up pushing his students to strive more in the subject and the impact may be so high that you may even end up digging so deep so that your life would turn around said topic.
Now, it is important to remember that a teacher has a number of classes, each of which contains numerous students. Furthermore, staying with the same teacher for many years is rare so they will not get to know you well enough to touch on particular triggers that would work strictly on you.
This means that an incredible teacher can easily be surpassed by yourself becoming your own teacher.
Discover more about yourself whilst learning a language and dig where you are attracted to.
Whether it be ants, planes, psychology, trumpet or any other topic, an interest that you may be the only one to know will be a great source of teaching material to yourself.
Of course, you will need support to correct you with mistakes along the way so studying with others may be useful but only you can provide yourself with the perfect material to study from.
Adapt your learning process to fit your style and create a further new you entirely fluent in said languages!