To extend it to a number of recent articles about kids (summarized):
--------------------
Kids who were told "you must be smart" when they succeeded were less likely to take on harder tasks later because they might fail, and seem stupid.
Kids who were told "you must have worked hard" when they succeeded tackled harder problems later and ended up learning better, because they perceived greater reward for doing better, not looking better.
--------------------
If you're smart, but you don't do anything you can fail at, you won't learn. Try. Fail. Try again.
--------------------
Kids who were told "you must be smart" when they succeeded were less likely to take on harder tasks later because they might fail, and seem stupid.
Kids who were told "you must have worked hard" when they succeeded tackled harder problems later and ended up learning better, because they perceived greater reward for doing better, not looking better.
--------------------
If you're smart, but you don't do anything you can fail at, you won't learn. Try. Fail. Try again.