Why does Ponyboy finally understand Darryl?

Ponyboy finally understands Darryl when he realizes that Darry's tough love stems from a deep concern for his well-being and future. Darry, burdened with the responsibility of caring for his younger brothers after their parents' death, pushes Ponyboy to Excel and stay out of trouble. This understanding allows Ponyboy to see that Darry's actions, though sometimes harsh, are motivated by love and a desire to protect their family. Ultimately, this realization strengthens their bond and helps Ponyboy appreciate the sacrifices Darry makes for them.