It is easy to confuse this principle of keeping within proper bounds with mediocrity, with being neither one thing nor another.
In reality there is a vast difference.
What the Jewish sages recommend is not only a middle way, it is a rejection of extremes in terms of a clear knowledge of how to keep everything, including the extreme, in its proper place.
Consequently, in general, there are no preconceptions about what is the correct conduct for all situations, since the correctness of a way of being is itself only measurable in terms of a specific set of circumstances that mayor may not recur.
There is therefore no possibility of fixing a single standard of behavior.
If anything is clear, it is that a rigid, unchanging way is wrong.
–Rabbi Adin Steinsaltz