Earlier quoted context omitted.
Umm... 20$ an hour, meaning 3200$ a month, would be quite a nice salary in a lot of Europe (Greece, Bulgaria, Romania, Poland, ...). You get people with BAs or MAs in comp science who have been developers for 2-5 years. While I'm sure some will say that 3.2k is ridiculous in country X, I personally met people in all of the above countries working for less while being more experienced.
20 USD/hour is not what developer earns, but what you pay for developer time. Overhead (buildings, managers, computers, toilet paper), sales commissions, taxes, and off time and eats big big part of that money.
20 USD / hour * 8 h/day * 21 days/month * 12 months = ~ 40,000 USD / year.
Of course, experienced ones don't receive that might higher salary either. About 5 years of experience would probably get you around double to triple the starting salary.