Because he died and then came back to life! How many of your favourite super heroes or villains can claim that, huh? Oh...wait.
Harry is such a diverse and insecure character. Even before his father took up the mantle of the Goblin, Harry was striving to gain his father’s approval. He never did.
A life of drug addiction, self worth and confidence issues, and the death of his dad tipped Osborn over the edge, and he became the third Green Goblin.
Unlike his pops, Harry tortured Peter Parker through psychological means. He followed an unconstumed Peter on the street, gliding behind him. He hinted to Peter that he would hurt his own family. Hell, he even created robot replicas of Peter’s parents and sent him all moody and broody – which lead into the clone saga.
Since coming back from the dead (cos he was healed by the goblin formula that heals his father – even though the thing that killed him originally was the goblin formula he fiddled with and took....yup) Harry has been a bit more subdued. When he’s not on the run with his half goblin half human son Stan, Harry can be seen using a taser to shock former police officers (even though he has enhanced strength) or running a coffee shop (even if he doesn’t know the ideal extraction times and dose levels for an Ethiopian Guji Sidamo five days off the roast).
Have fun with Harry Osborn this week – no one else seems to.