I will tell you upfront that I can mispronounce words. Sometimes, I may not intend to blemish the word, and sometimes I simply have never been exposed to the word and I am giving it my best.
Do you ever know the word, but it just comes out wrong? It is unintentional, and you know better, but it simply is not the word that is in your head, and you hear this other version when it rolls off your tongue. Once, I was having a conversation with someone and we were talking about the ability of a child. I knew I wanted to say precocious when I referred to the child; instead, it came out percocious. I slight slip of the tongue gave way to a non-word. There is no such word that I know that is spelled percocious.
By the way, precocious means when something has matured before its time.
I think not knowing how to pronounce a word is one reason why our oral language has been corrupted to simple, one-syllable words and slang words. That, and the ongoing problem of getting the young engaged in reading and exploring new words and ideas outside of their sphere. But then, that’s another story….