Deuteronomy 15:11

But forasmuch as the house of Israel will not rest in the commandments of the law, the poor will not cease in the land: therefore I command you, saying: You shall verily open your hands toward your neighbours, to the afflicted around you, and to the poor of your country.

I have already explained the needy will not be absent in the midst of your land [comment on 15: 7].

You must first give to your brother (i.e., your blood relative),

before giving to your poor (i.e., the poor in your family); and the needy of your land have precedence over the needy of another land. The common theme which connects this passage with the passage If your Hebrew brother be sold to you is the idea of “supply him with a bonus” [: 14].

FOR THE POOR SHALL NEVER CEASE OUT OF THE LAND. Commentators have said that the meaning thereof is that the poor shall never cease out of the Land at any of all times, for there will always be poor in the Land, for it was apparent before Him that they will not do [to make possible] what he said to them, But there shall be no needy among you, if only thou diligently hearken unto the voice of the Eternal thy G-d to observe to do all this commandment. But it is not correct in my opinion, for the Torah may allude to what will be but it would not explicitly prophesy about them [the Israelites] that they will not fulfill the Torah, nor would he have commanded them [to observe the commandments while foretelling] that they would always transgress them. Forbid it! It is only by way of warning that he mentions [their transgressions].
The correct interpretation is that he says that it is impossible for the poor to cease so that none should ever exist. He [Moses] mentioned this because, having assured them that there would be no needy if they observe all the commandments he said: “But I know that not all generations forever will observe all the commandments in which case there would be no need to charge you concerning the poor, for perhaps, at some time, there will exist poor and so I command you about him if he will be found.” He states out of the Land [for the poor shall never cease ‘out of the Land’] in order to allude to the entire habitation [anywhere on earth], for the promise that there would not be needy among us applies in the Land which the Eternal our G-d giveth us for an inheritance if we will fulfill there all the commandments. And now he said that it is possible that, at some period or at some place where you will have settled, there be found a poor man among you. For the meaning of the expression in thy Land [If there be among you a needy man … ‘in thy Land’] is like in all your habitations — within the Land of Israel and outside of the Land.

כי לא יחדל אביון מקרב הארץ, for it is basically unrealistic to assume that society is 100 per cent righteous, deserving, something which even Ecclesiastes 7,20 considered as an impossibility in this life.