Yes, that would obviously be best for discovering their individual reasons and I have discussed it with a few. But I'm not asking you why they come here. I'm asking why you believe what you said to be true and valid. I'm Mexican-American myself and your words just didn't sit right with me, it felt like you were just dismissing the whole idea of people living in Mexico...like a liberalized/opposite version of the "if you love Mexico why don't you go back!" We get whenever we show pride for Mexico (Implying that Mexico is a terrible place nobody should want to live or be proud of). I'm sure that wasn't your intention but its how it came off to me.

As for the substance of your response.

While mexico is certainly below in most metrics on averages, that includes wealth and cost of living averages. You shouldn't focus on just averages but the disparity between things like cost of healthcare and general living vs wages. Also being among the lower classes drastically increases your chances to be murdered in the US which isn't accurately represented in the average national statistics. It's not as simple as Mexico being a death pit and America is safe.