The children of Joseph spoke to Joshua, saying, Why have you given me but one lot and one part for an inheritance, seeing I am a great people, because hitherto Yahweh has blessed me?
As regards the first option, they were simply too lazy to do it, and, as regards the second option, "They saw only the chariots of iron, not the lush pastures and farmlands of the valley of Jezreel (Esdraelon), which was theirs by right of promise and which Joshua urged them to take.  What a contrast was their lack of faith to the bold, intrepid spirit of Caleb  (Numbers 13:30; Joshua 14:6-15)."[26]  Plummer was correct in the affirmation that the only reason the Josephites did not drive out the Canaanites and thus possess their possessions, "was that they did not trust in God, but preferred an unworthy compromise with neighbors who, however rich in warlike material, were sunk in sensuality and sloth."[27]