Daedalus' plan to escape works because e tried the wings on himself first and was satisfied that his plan would work. When they escape, they successfully flew from Crete but that plan of Daedalus made his son Icarus fell to death. Because of that, Daedalus' plan was the reason of Icarus' death, so he thought that it was his fault. He regret of what he'd done. Actually, it was also Icarus' fault because of forgetting his father's advise.