Dr.TenMa, who created AstroBoy, got upset and went over the edge, because AstroBoy did not grow. (not organically alive...). He could have had his "son" undergo periodic upgrades of his insides into "older" bodies, working to a goal of AstroMAN !
One criminal, named Skunk, complained that AstroBoy defeated all his crime efforts for 20 years, and now he was going to use Damdam against him. He even killed the guy who brought him Damdam's head, rather than pay him. Astroboy - 20 years -and still a little boy !
Dr.TenMa, who created AstroBoy, got upset and went over the edge, because AstroBoy did not grow. (no