Nuthin’
One of my favorite quotes is from Mr. Bill Shakespeare himself (I know we would have been, if not friends per se, at least friendly; and I do like to believe he wouldn't mind my familiarity):
"...THERE IS NOTHING EITHER GOOD OR BAD BUT THINKING MAKES IT SO."
This quote sums up something I find to be one of the greatest truisms of our reality, and can most certainly be applied to the question of what a good writer is. Grammar ain't nesessarily important to good wrriting, dontcha know. SPelling neither nor punctuation
Being a good writer depends entirely upon the READER. If one person (besides one's own mother, I feel I need to add) enjoys one's writing, one is a good writer. If a writer can touch one other person in this world, and make them feel understood, less alone, and part of the entirety of humanity; if one person is moved enough that they remember the words we write... that is what makes written work 'good'; and if what was written is good, so then is the writer good. Or bad? I dunno - what do you think?