I read a submission once that was very well written, if a bit bleak. I asked to see the whole manuscript, and the overall quality was excellent, but there was a problem. Not a single one of her characters survived.
Now I'm as fond of a dark outlook as the next moderately gloomy person, but there are limits. I also know that unrelenting fictional misery is very hard to sell to a publisher. (Note, I say 'fictional' - there has been a well-publicised trend for Misery Memoirs about horrendously abused children, but that seems to be waning).
I wrote to the author explaining that I loved her style, but that the plot was too dark, what did she want to do about it? She wrote back immediately - saying she had another manuscript in her drawer, and this one was much more cheerful, did I want to see it?
I settled down to read it, feeling optimistic. It was more cheerful. Marginally. The two main characters survived the ensuing blood-bath, …