I only put up stories that I intend to finish. If I end up not doing that, I delete them.

Advice for Fanfic writers and reviewers

ALWAYS:

Spell check and grammar check

Have a character in character, unless it's for a joke

Make a good title and summary (whether it be broad or narrow)

Respect other authors

Respect beta readers

Respect the creators and give credit to them

Update (at some point)

Say when you're going on hiatus

NEVER:

Make A Mary Sue or Gary-Stu (sometimes called Marty-Stu)

Say you suck at summaries or it's your first story in your summary

Use an entire chapter to say an announcement about your personal life

Make a character OOC for no reason

Forget to say when it's a crack pairing

Bash on other authors or your reviewers for their critiques--most of the time they're just trying to help you out, and if the person does leave a nasty review don't satisfy them with an answer

Insult other pairings if they're included in the summary

Attach the wrong rating/genre to your story or forget to include any pairings

Forget to spell or grammar check

Make enough mistakes to confuse the reader

Hopefully this helps! I got a lot of these from The 27 Commandments of Fanfiction and added a few of my own.