My ancestors came here because life in the "Old Country" was so bad that braving the crossing of the Atlantic in cattle class on a ship, coming through Ellis Island, finding out that working in New York wasn't much better, and finally landing in the steel mills and coal mines of Western Pennsylvania was a step UP--but not by much.
Those same ancestors also stood in front of bullets from Pinkertons because that was preferable to allowing their working conditions to continue.
The fact that immigrants move is generally a sign of how shitty the place they are leaving is, not necessarily a sign of how good their destination is.