What does "decent at writing mean"?

When you start digging in you realize that (like most things) there are multiple different definitions. LLMs are very good at putting together a lot of words that are spell correctly with grammatically correct sentences (better than me - though I'm particularly bad at this). However people often want to add other things like "correct" (the facts are right...), or some notion of not using too many words. LLMs tend to not be as good at those.