Why do immigrants never go back to their country if they're so proud of it?

I don't understand that either. I was born an Indian Hindu. There is indeed this obnoxious and immense pride that they have but they also just want to somehow migrate out of this country. And yes they're racists towards Muslims and blacks. But that's something that's not just seen in proud Hindus but also proud Muslims, Mexicans, etc.. Since I'm an Indian I know the deep conversations that they have too. They'll be making fun of American food and the culture and almost everything. And yet they don't want to come back.
And when they come back to India all they would do is complain about India.

What does that tell you ? People from all cultures are told that they're the best and that they're great. When they start to see that some other place is better they can't cope up with that. So they start trying compare everything in their culture to that other culture believing that the only way they can feel superior is by making their culture seem superior. But the ones who are from the most developed countries never compare their culture to any other culture.

Funny things are happening in India. They credit almost every invention back to some Indian mythological stories that we were taught as kids. It's like saying Leonardo Da Vinci is the inventor of Flying vehicles.
Every Indian becomes proud when someone from India becomes a CEO of an American company but what they fail to see is that that person does not have an Indian citizenship anymore. They have gone beyond the bigotry.

I don't blame a particular community for this though. It's a general human behavior. You have to make others believe you are great when you very well know you are not.