The tragedy of Antigone can teach readers to get things right the first time before it is too late to fix it. In this story, when Antigone illegally buried a dead body, Kreon wanted her to be killed. He did not like the idea of anyone breaking the law, even if it was the right thing to do. In pages 35 and 36, Kreon's son Haimon tried to convince his father that he was wrong, and Antigone only did what was right. He believed she should not be punished. Kreon did not agree with his son, and they were mad at each other.
However, eventually, on page 64, Kreon realized he was wrong, and tried to save the girl. He was too late though, for she had hung herself. Haimon was devastated with Antigone's death and tried to kill his own father, but then missed and killed himself instead of trying again.
If Kreon would have listened to what people were trying to tell him, that punishing Antigone was wrong, then he could have had it right the first time and not have had to deal with yet another death in his family. However, he really was too late, and had to face the death of his son, which even lead to the death of his wife, who hung herself, like Antigone.
This can be a tragedy that people learn from. People can learn that if many people are telling them that something is wrong, and they can kind of tell that it might be wrong too, they should make sure to not make the mistake of going through with whatever it is that people are telling them not to do. Otherwise there might be too late.