When people have no hope of not making it as a permanent resident or citizen, their incentives to perform well are not as high. Also immigration is a global market, you compete with other countries that might offer better conditions so you lose on the best workforce.
I don't know the overall ratio, but my experience working with many immigrant workers is that they had no real intention of staying and instead are just arbitraging cost of living between [rich country] and [poor country] for their family back home. Emphasis on home.
Sounds like you have a really limited interaction with immigrants. I’m lifelong immigrant (4 different countries) in every single one of those countries majority of immigrants want to stay. Permanent residency is a constant conversation topic. There are definitely immigrants thinking like your explanation, but definitely a minority. .
There are all sorts of reasons people emigrate. It varies based on the jobs they’re doing, where they’re from, and where they’re going. And whatever their intentions, things change. And, why must there be a universal answer for everyone?
There are 40k naturalisations each year (a similar number relative to population as in the US). Around 13% of the Swiss citizens have acquired the nationality via naturalisation (8% in the US).
How many people born in CH never become Swiss? Because for the US, that number is ~0%.
And before you say: "well the US have different rules", well, ok, but then don't compare us to the US on the other number either, compare us to other EU countries with similar types of rules but different implementations.
CH has stricter naturalization laws than many EU countries and CH has mandatory military service which discourages many males from naturalizing, even those born in the country.
About one third. That would bring the fraction of naturalised foreign-born citizens in line with the US (which is also a kind-of-hard place to get citizenship, that's true).
> CH has mandatory military service which discourages many males from naturalizing
That doesn't make it difficult, it makes it undesirable and suggests that many people could get it but choose not to.
https://www.amnesty.org/en/location/middle-east-and-north-af...