"working on my craft"

[tlove3]

where did this come from? Butch obviously loves it "comes everyday and works on his craft"

I keep hearing multi millionaire pro athletes use this phrase and it just seems weird to me. I can't imagine any other profession where someone at the very top would say (in a yearly or quarterly review or something) "you know I just come in every day and continue to work on my craft"

Is this relatively new? Was it Lebron?

-Triggered