Initially, I didn't know what words were, so the point of them was lost on me completely.
Later on, after learning to talk, started having more and more trouble with it because it had always been extremely difficult/painful/etc. And got gradually harder over time (with intermittent periods of speech and non-speech where the non-speech just got more and more frequent). So now, I don't, because I can't force the process of finding words that match my thoughts, speaking those words (while keeping to the ones that match my thoughts), and so forth, probably a combination of a motor thing, overload thing, painful speech thing, word-finding thing, multi-tasking thing, etc. all building up into a much larger thing than any one of those things are on their own.
Be aware that it can be any number of a huge amount of different things for different people. Some people, very unlike me in my early years, had never had any trouble at all with receptive language, but had trouble with the act of speech, for instance, just couldn't get words to come out of their mouth on command.
_________________
"In my world it's a place of patterns and feel. In my world it's a haven for what is real. It's my world, nobody can steal it, but people like me, we live in the shadows." -Donna Williams