In Conan the Barbarian, the plot seems to have the following sequence:
Thulsa Doom destroys Conan's village and enslaves women and children.
Profit motive for the latter - he can sell the slaves.
Conan's buyers make the children move the milling wheel
Profit motive for the buyers: labor to produce energy for milling (we'll leave aside the economic efficacy of that specific plot device).
Conan's buyers sell the muscled-up Conan to "Red Beard" (he's never named).
Profit motive for the buyers - get money for Conan, presumably. Or something of value.
Profit motive for Red Beard - Conan is good gladiator material, and gladiator slave's owners win money on the fights (we see that happen in the movie).
Red Beard teaches him how to fight locally.
Profit motive - he fights better, more winnings.
Red Beard takes Conan to the warmasters of Khitai (China, though they look very Mongol), to be taught warrior ethics, warrior skills, poetry, writing, philosophy.
Profit motive - WHAT PROFIT!?!?! Red Beard releases Conan into the wild - forcefully - the moment Conan finished his education!
Why in the world would Red Beard kick Conan free in the first place? Never mind first spending a - presumably - considerable fortune upgrading Conan with Asian Martial Arts and Crafts training?