David Johnston wrote:

I've been considering this issue ever since it came up on R.A.A.F.
Argument by analogy is a dangerous business of course.  We aren't
"guests" in the original author's work, more like burglars.  We can
hardly regulate the actions of fanfic writers since we are basicly
scofflaws of a minor sort.

That being said, I'm always puzzled and repelled by fanfic written for
no particular purpose except to kill and corrupt the heros of the
original series.  If you like the series, why destroy it, even on an
imaginary level?  If you don't, why are you writing about it?  I suppose
it makes sense if what you liked about the series were the villains.

  There are a couple other reasons for fics like this.
1)  The author feels that this is the direction the series should take.
People who feel that the "heroes" are actually the villains of the series
tend to write in this direction to reflect the way they see the series.
2)  An idea takes hold of an author and won't let go.  This is probably more
common than one might think.  A lot of fanfiction ideas come from playing
the "What if" game and sometimes you get one of those "What if's" stuck in
your head and have to write about it.  This kind of fic tends to be somewhat
angst ridden and isn't too much fun to write, especially if you like the
characters you're affecting.

There are, of course, exceptions.

Just my opinion,

AJ