Granting a Greencard to non-resident aliens who stay in the U.S. is very hard. The government should to pick foreigners with better qualities to grant a green-card VS. someone who doesn't speak the main language/no education.
Unfortunately, the immigration laws seem old and dated. The most two popular ways to get Permanent Residency:
1) To get married to an American Citizen
2) Win the Lottery
There are few other options such as:
3) Through work (complicated process)
4) Religious/Humanitarian
5) Political Asylum (Prosecution must be provided. Like what Snowden did in Russia)
Green Card winners usually don't speak English.
Most people get married as FRAUD to get their Residency with cash money (UNTAXED), (Unfair to who wants to play fair)
If you agree, please vote.