Answer :

Jobs
Money
Healthcare
Family

Immigrants come to the US for a variety of reasons. A lot of people left oppressive governments and came to America for freedom. Some came to find a better life for themselves and their family as their lives were destitute in their own country from famines, wars, droughts, etc.  Some came to escape religious or political persecution. Unfortunately, some have even come to hide among our masses from crimes they committed in other countries. In the early years, many came because of hearing how people became rich in the gold mines and they thought they would also.