There's a whole bunch of factors that affect it. It's actually Eastern cultures that tend towards external factors (relative to us North Americans). But, in general, everyone focuses more on the individual factors than they should: it's called the Fundamental Attribution Error.
I've learned a bit about this recently in a Coursera class on social psychology. I tried to attach the lecture video but you need to be in the class to watch it. I recommend joining though - it's fascinating (and free).
This isn't meant to be a hippie, voodoo, "all you need to do is focus on success and it will come" message. There are real handicaps.
But there's also tons of people hurting their chances of success in order to protect their egos. It's not just about perfectionism (although that's one manifestation).
Which "real burdens" did you think were targeted that shouldn't have been?
I usually ignore critical comments, but on deeper thought that tagline comes off a lot douchier than it did it my head. There's a better word for what I'm trying to convey than "winning" but I can't come up with it.
Now that the tagline's changed, you can go back and take some life advice ;)
In this case, eating seconds is not a self-destructive act but an example of cognitive dissonance. Maybe it's not true for everyone, but most have the feeling that they're doing something wrong/unhealthy when they indulge in too much dessert, but they have the temptation to do it anyways.
That's cognitive dissonance. Self-destructive behavior is just one example of a weird way we deal with that tension (in this example, maybe that's the person who says "I have bad genetics, so it doesn't even matter anyways!" before stuffing their face).
Re: Are you self-handicapping? Probably not. You've got a real disadvantage. BUT that doesn't mean you should hold yourself to any lower of a standard. I find that a useful heuristic is to automatically answer "yes" to this question. In other words, if I told you authoritatively, "YES, YOU ARE SELF-HANDICAPPING - SNAP OUT OF IT" what would you do differently? Usually, whether it's true or not, those are the right decisions.
Re: Exceptional. I'm sure you are. Exceptional is a vague term and that can lead to big ego swings. We can all find evidence that we're "exceptional" and "non-exceptional" every day. The trick is to realize that assuming that your exceptional innate abilities will lead you to success without work is a myth. Just keep hustling. Excellence is a habit, not a trait.
This started off as a piece about Jobs' "Real Artists Ship" quote and slowly evolved. "Build it and Ship it" really is the entrepreneur's corollary to this whole line of thinking. Glad you picked up on that.
I've learned a bit about this recently in a Coursera class on social psychology. I tried to attach the lecture video but you need to be in the class to watch it. I recommend joining though - it's fascinating (and free).
https://class.coursera.org/socialpsychology-001/class