The very obvious reason is that a junior dev is by definition replaceable (because he can't work on his own), and thus makes no sense hiring full time locally -

The very obvious reason is that a junior dev is by definition replaceable (because he can't work on his own), and thus makes no sense hiring full time locally - better (cheaper) be outsourced to India or Ukraine. Outsourced people are unreliable, but with junior ones, this is OK, some trial and error is quite affordable. Or better yet, you can hire a senior in Ukraine for the price of junior in the U.S.. And junior ones in Ukraine just do ghostcoding for the seniors until they can find clients of their own.