Why does it say that he never angered him?
Rashi: This teaches that one who withholds rebuke 1 from his son, he brings him to death.
Radak (5-6): Even though he knew that his father intended to make Shlomo king, he thought that his father loves him, since he never angered him. He thought, I will make myself king; if David does not do evil to me, I will reign.
Malbim: This explains why he was not afraid of his father.
Torah ha'Temimah citing the Vilna Gaon: Having such a great father as David did not pain him (break his heart) to say to himself 'why did you do this?' Therefore, he was not proper for kingship.
Shemos Rabah (1:1): Because he never afflicted or rebuked him, he went on an evil path.
Why does it say "v'Gam Hu Tov To'ar Me'od"?
Rashi: He was beautiful like Avshalom, about whom it says "uch'Avshalom Lo Hayah Ish Yafeh" (Shmuel II, 14:25). This caused both of them to be haughty. Malbim - he did not fear lest Yisrael not agree that he be king, for he was confident to find grace in their eyes due to his beauty, just like Avshalom did.
The verse implies that his mother (Chagis) gave birth to him after Avshalom. Avshalom's mother was Ma'achah!
Rashi: She raised him to go on the same [evil] path that Avshalom's mother raised him. 1
Gra (Divrei ha'Yamim I, 3:2): It teaches that his birth was after Avshalom (albeit from a different mother), so he was the fourth, and therefore he aspired to be king. Amnon and Avshalom were dead, and Kil'av (his only living older brother) always learned Torah and was not interested in being king (Brachos 4a).
Shemos Rabah (1:1): Since Avshalom went on an evil path and his father did not afflict him, also he went on an evil path.
