Moses has led Israel out of Egypt and through 40 years of painful Wilderness journey. His leadership has been tried and tested. The people have followed him most of the time and when they have not then he sought The Lord on what to do.
He would not make the journey into The Promised Land because of his own sin in not following the Lord's commands. Many read the Numbers 20 account of Moses striking the rock instead of speaking to it and think this is a petty infraction. Yet, God holds leaders to a higher standard. The Word says this in Titus 1:5 and James 3:1. Why? Because others watch the leader and pattern off of them. We must live as examples of faith and trust in God or we can lead others astray.
This does damage Moses' legacy but it doesn't destroy it. Why? Moses doesn't quit once his mistake is made and he is punished. He continues to live a life of faith and trust until he dies. He begins the process of preparing the people to enter the land without him. He prepares Joshua to lead the people. Joshua has been a military leader for Israel but this is still a big jump. The people would need to follow Joshua with the same zeal that they followed Moses (most of the time).
Moses didn't get to enter the land but the people that he helped prepare did...that is legacy...your work continuing after you are unable to perform it. What would your legacy be if today was your last? Good? Bad? Both? Who are your preparing to do things that you do - in your family, in your workplace, in your volunteerism? It matters. It is a part of the stewardship of life and it is never too early to get to work on it.
Pray for guidance, live as an example, intentionally pour into others. Leave a legacy that is above reproach!