You may know a language (say Finnish) enough to talk to a Finn, but if for this you have to keep in your bag a dictionary (or to search in your mind for the right word), if you are not fluent in reading in others' mind you only are brought to fake some competence you don't possess. You become an actor, you cannot really be sincere.
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Ever tried. Ever failed. No matter. Try Again. Fail again. Fail better.
--Samuel Beckett