I should clarify my previous post thusly:
1. I do find the material of math interesting. Unlike psychology or economics, I'm not usually actually curious about math. I certainly don't feel curious about unresolved problems in math. But once I see what's there, I do tend to really enjoy it. So in terms of interest, math is maybe like art for me. I'm not actually curious to see new art, but if I find myself in a gallery I will often super enjoy what I find there.
2. Is math a relative weakness for me? My best guess is that it's somewhere in the middle of my talents. But it may be only that I have gotten far enough in math to see my own limitations, while only skimming the surface of other subjects. It may be that I only imagine that I would kick more ass in some other field. I find that quite plausible. Also, of course, the nature of math is such that it's somewhat objective whether you're succeeding or failing. I might be able to wrongly believe that my essay on Macbeth is a work of genius, but a proof either works or it doesn't.
3. Do I prefer subjects I fear failing at? Perhaps not. I think it's more likely that my disinclination to work means that I'm more likely to work hard if I'm moderately afraid than if I'm pretty confident, and of course, as I've mentioned before, more work = more enjoyment, at least for me. (Is this true for other people? Do you prefer a difficult 2-hour hike to an easy one, after it's all over?) There is also kind of no superficial level of math. You can read a book like How the Mind Works and feel like you have a grasp of cognitive psychology, but even the equivalent lay math book will require work and thought to grasp (again, at least for me). You either work hard and get something out of it or you don't and...don't.
So I guess what I'm saying is, contra modern wisdom, all-or-nothing thinking and a slight lack of self-efficacy are drivers of my math success.