Summary: It could have ended worse
Krypton was dying. It was too soon in its history for a planet to die, but death doesn't keep a schedule. Kel-El had no choice but to send his son somewhere else. Somewhere he could survive.
He survived, found and raised by a loving family. One that didn't mind that he was a cripple, body and mind painfully limited. Not everybody was as understanding, and the boy grew up an outcast. It was another layer of pain added to the loss of his first home.
As soon of his powers manifested -just as the scientists had predicted they would- he left Mars. There was no intelligent life on the blue planet, but he didn't mind.