I like that phrase, "native ability" better than "talent." "Talent" has a lot of baggage and from what I've seen, you're right in your observation that people tend to view talent either 100% or 0%. I have seen a lot of people, including my own classmates from grade school and some of my students suffering from this kind of mentality. SeventhProphet illustrated it well in this statement:

It's just... my whole life everyone told me i was this genius super child who was going to do great things, and i guess i caved under the pressure.

Now, I have personal experience with this as well, but in the end, how does this "everyone" know what a "genius super child" is vs. a kid with a bit of talent and intelligence? Heck, the people saying those things might even be pretty dumb. Today, it's pretty common for people to be use hyperbole for relatively common things, as illustrated in this Louis CK bit. I really think that when people say these things about kids, it creates this expectation of wild success that simply can't be lived up to.

To better see what I mean, check out these two articles, one from the New York Times Sunday Magazine about how kids handle pressure, and one from the New Yorker about the perils of praising kids too much.