If a scientific research group of, maybe, a dozen members, A to L, decides it badly needs three foreign researchers with special skills then, other things being equal — e.g. funding — then the leader, A, will invite them. Because such a research group has a precise objective then new members M, N and O will find their acceptable rank order fairly quickly.
Not so if, by any chance, the new group, A to O happen to live near one another and develop a rich social life between them. If A to L tend to come from one culture — the indigenous one — and if M to O from another then there are likely to be problems. This is due to the enormous number of differences in the way that each group expresses itself — trivially or substantively.
There has been a cloudburst of major discoveries about human nature in the last few decades. The quicker these get into the curriculums of schools and universities the better.