Zoro and Sanji are clones
Sanji was made in a lab but didn't born as expected like his siblings, considered a failure
Zoro was made in a lab by the Ancient People in an attempt to bring back Ryuma, but he borned malfunctioning, biting swords for no reason and trying to fight with them, losing 2000 times to a girl who lost to stairs, getting lost even in a straight line
Pirate King's wings: Failures who became gods lets goo