Moses was raised in Pharoah’s court, likely given the best education in Egypt and he was a natural leader. (Acts 7:22).
And I think he had an issue with pride.
When Moses rose up and delivered a fellow Hebrew from the hand of an Egyptian, the Bible says “he supposed” the Hebrews knew “God was granting them deliverance through him.” (Acts 7:24-25). They didn’t, but Pharoah did and Moses fled.
Moses’s failure and forty years of shoveling sheep dung in the wilderness so changed Moses that when the Lord finally did call him, all Moses could do was think of reasons why the people wouldn’t follow him. (Exodus 4:1, 10).
By the time Moses had led the Israelites out of Egypt the Bible would say of of him: “Now the man Moses was very humble, more than any man who was on the face of the earth.” (Numbers 12:3).
When Moses was full of pride, he was not useful to the Lord. The more humble he became the more useful he was to the Lord and the better leader he became. And Moses was a great leader, one of the greatest ever. GS