Fandom is a subculture that grows up around people who are passionate about a work when the rest of the world isn't.
If the work is part of the dominant culture, nobody has to build a fandom around it. The Well-Tempered Clavier is assigned to every piano student -- nobody has to organize clubs to listen to Bach in secret.
To have a fandom, a work doesn't have to be bad. It can just be overlooked, forgotten, or left behind by the mainstream. Gilbert and Sullivan operas are pretty good, but they have a fandom made up of old-fashioned Anglophiles and intellectual showoffs. (I'm one of them, naturlich.)
It helps if there's something totalizing about the work itself -- if the author insists that it should change how you see everything about the world, then those who like it will make fandom part of their identity. (See: Wagner, Rand, Kerouac.)
I think "goals" are the wrong way to look at it.
Very few people have a complete, coherent system of terminal values. The few who do usually seem to suffer from their excessive rigidity. I can't commit to an exhaustive set of goals, all the way to the end of my life. I've had to discard and change my plans too many times. What looks like a great idea today may turn out to be fruitless on inspection.
Instead of goals I think about resources. I don't know specifically what I'm going to want to do, but whatever it is, money will be helpful. As will health. And human capital. And a track record of accomplishments.
When a goal isn't a resource, it usually turns out to be a fake goal. "I want to learn Latin." Well, if learning Latin isn't going to help me with anything, then guess what? I'll never get around to learning Latin. It's just an empty aspiration. Learning awk, however, isn't an empty aspiration -- I learned the hard way how badly I need it. Awk is a resource.
It's not a perfect distinction. Sometimes a resource looks like a mere aspiration because its usefulness is too far away in time. Asking "is this a resource?" will tend to bias you towards what you need most now. But it's not a bad algorithm. (I think of it as gradient ascent.) You get done what you need to do, and you worry a lot less about what you vaguely think you should be doing.
I've learned a lot about the transience of moods by keeping track of them via Moodscope. I almost never have a similar mood two days in a row. Mood is weather, not climate. You are not one single person -- different people pass through your brain, many times a day. Being aware of this hasn't kept me from having bad moods, but it has made me stop believing in them, if that makes any sense. I don't take them literally. I think "Oh, there's that thought again. It feels true now, but it'll feel false tomorrow, and true again next Wednesday."
Being realistic about the brain means making your peace with flux.