Needless to say, I hate writing rejection notes. Sometimes the stories get rejected because, although the story is well written, it's just not to my taste. I'm not much of a fan of slow, moody pieces - and this includes classic style ghost stories; traditional epic fantasy has to have something special for me to say yes to it; romance? bah, humbug!
Give me snappy, fun stories. Things that move fast. Anything with sarcastic humour sneaking around it. Adventures and monsters and really weird things. Things that made me laugh out loud. Things that entertain.
Of course, sometimes it's just a case that the author is taking forever to get to a point, using 8 paragraphs where 2 would do. And over-long sentences... oy, I hate those.
Get to your point. Don't waste words. A little atmosphere building is fine, but there comes a time when you need to get on with the story.
And, at the moment, short stories have a better chance than longer ones.
Rant over :->