For those who might have missed it, one of the authors (Ericsson) is the same person who originally came up with the &quot;expertise requires 10,000 hours of practice&quot; idea that Malcolm Gladwell later popularized.  Unfortunately, Gladwell mangled it as badly as he mangles everything else.  As I had to point out on another story here recently, Ericsson was talking about 10,000 hours of highly focused and disciplined practice, carefully analyzing and correcting errors etc.  Thanks largely to Gladwell, many people have dumbed that down to 10,000 hours of any old thing, and it&#x27;s no wonder that they find the idea highly questionable.  The original makes much more sense.