Article: The major issue with the term Hellenistic lies in its convenience, as the spread of Greek culture was not the generalized phenomenon that the term implies. Some areas of the conquered world were more affected by Greek influences than others. The term Hellenistic also implies that the Greek populations were of majority in the areas in which they settled, while in many cases, the Greek settlers were actually the minority among the native populations. The Greek population and the native population did not always mix; the Greeks moved and brought their own culture, but interaction did not always occur.

Now answer this question: How often did Greek population and natives mix?
not always