Scrooge was visited by four spirits: his former partner, and by agents of Time of past, present, and future who showed him how the interactions of many, only human, affect each other, only human. The last spirit to visit him showed him specifically how his actions affected others and how others would, in turn, affect him.
Scrooge had to be willing to listen to what the spirits had to say to him; or else all would have been naught. Being willing to listen to the spirits, Scrooge learned and changed.
Sometimes people are unwilling to listen and to change. They see the size of the change that might come over them, and plead for a stop they're only human, after all. Sometimes, that word only presents a barrier to change in and of itself.
Only human, Ebenezer Scrooge from that point on was a totally different human, far different from what he was before. He was wise enough to listen to the spirits, and to change his behavior, realizing that what he did was important to the lives of so many others and realizing the great potential that is stored in being human.
"He became as good a friend, as good a master, and as good a man, as the good old city knew, or any other good old city, town, or borough, in the good old world. Some people laughed to see the alteration in him, but he let them laugh, and little heeded them; for he was wise enough to know that nothing ever happened on this globe, for good, at which some people did not have their fill of laughter in the outset; and knowing that such as these would be blind anyway, he thought it quite as well that they should wrinkle up their eyes in grins, as have the malady in less attractive forms. His own heart laughed: and that was quite enough for him." (Charles Dickens, A Christmas Carol)
A person could have a worse epitaph than that.
Scrooge as a role model? Think about it. A few more Scrooges just might make another, better, world possible.