There are definitely a lot of sadly underappreciated fics, but I wouldn't go so far as to suggest a lack of hits is the author's responsibility. Some of the fandom-famous fics really are fantastic, but I've also seen a lot of incredible fics that never quite got off the ground in terms of hits. Given that fic is mostly done out of love of writing and/or the subject and is not-for-profit, I don't think it's really the author's job to try to recruit people to read their work. If the author isn't already established or famous in fandom, there's a large element of luck involved in whether or not their story ever becomes popular. It may not be fair, but all one can do is write and hope for the best. Or at least that's my philosophy, based on a ton of fic reading and periodic pondering of the vagaries of virality on AO3.