beauty
There's something about beauty that turns people into muses. Not that non-beautiful people cannot be loved, but BEAUTIFUL people have that something extra that makes their admirers just that much more creative. Beautiful people, I think, know they are loved more so than non-beautiful people. Confidence... But not that confidence that comes from knowing EVERYONE thinks you're gorgeous... The confidence that comes from the one YOU admire admiring YOU. Move beyond that... Assume every ugly person and every beautiful person has someone that loves them... The love between the beautiful person and their admirer is expressed better (ie more often, more creatively, etc) than the love between the ugly person and their admirer. This is just a hunch but from my non-scientific observations it seems to ring true.
Also, can you be called a muse if what you inspire is not positive? If you inspire someone to write something, are you a muse if that something was awful? I don't mean badly written or a letter of hatred to the possible muse. I mean, if what was written was written well and was not a letter of hatred but just a plain old disgusting piece of writing. Does the label of muse depend on whether the writer knows what inspired it? On whether the muse MEANT to inspire or not? On whether the inspiration was positive or negative, beautiful or ugly, well-done or sloppy?
Also, can you be called a muse if what you inspire is not positive? If you inspire someone to write something, are you a muse if that something was awful? I don't mean badly written or a letter of hatred to the possible muse. I mean, if what was written was written well and was not a letter of hatred but just a plain old disgusting piece of writing. Does the label of muse depend on whether the writer knows what inspired it? On whether the muse MEANT to inspire or not? On whether the inspiration was positive or negative, beautiful or ugly, well-done or sloppy?