From someone who has studied many languages:

Language is fraught with errors. I could ask three people what the meaning of the word "voluntarism" and get three different answers. Language is a weak form of communication because none of us have a perfect, dictionary mind, and we must assume that we both know and understand the formal meaning, emotional meaning, and colloquial meaning of each and every word we use. And then, we have different languages too, on top of all of that! Put a seven-word sentence together and you have at least seven possible ways of misunderstanding with your collocutor.