Upvote:1
http://en.wikipedia.org/wiki/Ekalavya
Ekalavya - Indian mythical character whose hard work / persistence made him one of the best archer.
Upvote:3
Maybe Stakhanov could be what you are looking for.
Persistence: He broke mining records several times.
Constent improvement: Even though his character might be mythical (probably forged by propaganda), he really improved mining techniques as an engineer, via the separation of tasks.