> Think about the reader -> I've often heard people say "write for yourself"
Here's the truth, everyone who tells you they're writing for themselves is lying. If they were writing for themselves, they wouldn't publish it publicly.
It seems pretty unnecessary to call such people liars. Surely they know their own minds better than you.
Anyhow, it is not too difficult to understand the “write for yourself” aesthetic, if you are willing to make the effort. I think Jane Espenson describes it best: http://www.janeespenson.com/archives/00000619.php
Why cannot both be true? You write something for yourself, but also publish it in the event that it benefits someone else.
But even so, I think the context here was more like "write the sort of book you would like to read", not strictly "write the book so that I and I alone can then read it".
"Write for yourself" is shorthand. In part, it's to get an individual writing. After a hundred pages of short stories and essays it might evolve to a more restrictive "find your voice".
Once a writer finds a consistent voice, with recurring themes and techniques, the call to write for oneself is unnecessary. There's enough material for an editor to work with that more specific and constructive criticism can be given.
Maybe we should interpret that advice as "write about something that is interesting to you"? You could write about something that you find genuinely interesting, but in a way that makes it accessible to your audience (which isn't yourself, unless you're wrinting your personal diary).
Here's the truth, everyone who tells you they're writing for themselves is lying. If they were writing for themselves, they wouldn't publish it publicly.