Hand-me-down sandboxes: why write fan fiction if you don't know the source?

In a recent post, esorlehcar asked, "Why do people write fanfic for shows they haven't watched (or books they haven't read, or movies they haven't seen, or whatever)? Even beyond having no reliable frame of reference for the characters, even beyond the inevitability of producing badly characterized fic, why would you want to?"

This is a question I've been giving some thought to, because technically, I've done it or something like it twice now. In reading the comments on her post, I saw that almost everyone who had responded to her expressed negative opinions of a) the motives of anyone who would write for unfamiliar fandoms, and/or b) the quality of the resulting writing. I decided to take a stab at articulating a minority opinion -- I think it's an understandable choice to write fanfic for unfamiliar source texts, and I think it can yield genuinely good stories. I'm not doing this to defend myself (though I admit the impulse is there), but because I'd like to contribute to a broader view on why people become fannishly active, and what the purpose and pleasure of writing fan texts is. That said, I am going to draw on my own experiences, as a reader but mostly as a writer, because that seems to serve my purposes best -- a first-person perspective on this question, instead of a third-person analysis. As a result, I know some of this may come off as arrogant or self-centered; that's not the intention behind it.

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