What does 2 Samuel 1:10 mean?

So I went over to him, and since he was already dying and couldn't survive, I finished him off. Then I took the crown from his head and the bracelet from his arm, and I brought them here to you, my lord. 2 Samuel 1:10 - Modern Text Bible

(The Amalekite is telling David how he killed Saul, claiming he did it as an act of mercy and brought Saul's royal items to David, expecting a reward.)