What clifies someone as a good writer?

For a YA novelist, it's mostly about the actual writing and the entertainment provided. By the actual writing I suppose I do actually mean the ability to make you feel emotion. No one really cares if your grammar is correct 100% of the time. Spelling better be correct by the time it gets through editing for publication. Syntax is fuzzy to begin with, and ought to be treated more by authors preference and comfort. Words have flavor. Some make you feel things, others just feel nice on their own. Emotion is a form of entertainment. YA novels are known for being 'light' so far as thinking goes. No one expects any deep thinking for a YA novel, so ability to make someone think isn't really necessary, although it is nice if you can add that in there.