Exo 18:23-24, 23 If you do this, God will direct you, you will be able to endure, and all this people also will go to their place in peace. 24 So Moses listened to the voice of his father-in-law and did all that he had said.
It was humbling for Moses, a man God spoke to directly to listen to an old man from a pagan country who had come to believe in the God of Moses. He did not despise this advice, he saw the reasonableness of what his father-in-law proposed and was confirmed by the Lord and he resolved to put it in practice.
One man could not keep pace with the number of constantly arising cases leave alone having more time for himself and family. This same Moses at a later time would feel the weight perhaps having resorted to his old ways of trying alone, Num 11:14 “I am not able to bear all these people alone, because the burden is too heavy for me”. And God had him anoint 70 elders to assist him carry the burden. It is therefore far better to set able people to work than attempt to do the work alone, that is wisdom. Pro 9:9 “Give instruction to a wise man, and he will be still wiser; teach a righteous man, and he will increase in learning”. God instructs us by His word and through others where we cannot make discoveries for ourselves.