This is the nature of the Children of Israel. They objected despite the fact that Allah (swt) had told the prophet who would be their king. He told them that Saul would be their king; yet, their response was:
(… قَالُوا أَنَّىٰ يَكُونُ لَهُ الْمُلْكُ عَلَيْنَا وَنَحْنُ أَحَقُّ بِالْمُلْكِ مِنْهُ وَلَمْ يُؤْتَ سَعَةً مِّنَ الْمَالِ ۚ .. ) (..How can he have kingship over us while we are more worthy of kingship than him and he has not been given any measure of wealth?”…): Saul was never a descendant of Benjamin nor a descendant of Levi as was claimed about him. Therefore, they rejected him because he is not of a certain descendance and said.
Just compare the divine standards to those of humans. They wanted him to be of a certain descendance and have wealth. The nature of humans is still unchanged even today. They are after the people of wealth rather than the people who enjoy ethics and values. Their standards are material, and so are the Children of Israel. This is a lesson for humans so that the one who has wealth is not the one who reign over people. This must the one who has values to reign over people rather than the one who has the wealth. Then, their prophet said:
(… قَالَ إِنَّ اللَّهَ اصْطَفَاهُ عَلَيْكُمْ وَزَادَهُ بَسْطَةً فِي الْعِلْمِ وَالْجِسْمِ ۖ .. ) (..He said, “Indeed, Allah has chosen him over you and has increased him abundantly in knowledge and stature…): A strength of knowledge and a material strength of stature; so what was the justification of the prophet? It is that Allah (swt) had chosen, and such choice had been based on knowledge and the beneficial strength controlled by the knowledge. This is the reality of our religion.
(… وَاللَّهُ وَاسِعٌ عَلِيمٌ ) (….And Allah is all-Encompassing and Knowing.”): All-Encompassing means that everything in this earthly life is under His control, and He (swt) is Knowing of what is beneficial for mankind.