That's right -- rocks. Not virgins or children, but rocks. Motherless deposits of sediment whose disappearance from the earth results in the shedding of precisely zero tears. King Dodongo lives in a hole in the ground, eating rocks and minding his own business. And Link breaks into his house and throws him into the lava, for the express purpose of proving to the townspeople outside that he is a real man.
If there's more to manhood than destroying things, we don't want to hear about it.
Granted, Dodongo isn't defenseless -- he breathes fire and has giant teeth -- but he isn't hurting anyone. He isn't even bothering anyone. He's just sitting in his circle pit, eating rocks. And it isn't like Link stumbled into Dodongo's cave and now has to fight his way back out to stay alive -- he went out of his way to go in there. Killing Dodongo was an errand in his planner.
But Dodongo is just one example of the bosses in the Legend of Zelda series whose only crime appears to be being trapped in a room with no exit. Take a look at A Link to the Past's Helmasaur King:
Because neither he nor Link can be bothered to look at each other.
Helmasaur's left foot can barely fit through the only way out of that entire chamber. Either the keepers of that particular dungeon built the entire thing around him, or they brought him in when he was a baby and just left him there for a decade. The same goes for his successor, The Wind Waker's Helmaroc King, who is really just a great big bird somebody trapped in a battle mask.
"Somebody take this goddamn thing off me!"
Twilight Princess makes the situation even worse. Nearly every boss in the game is just an enemy that's been poisoned and transformed against its will by a piece of the Fused Shadow. So now Link is basically fighting captive animals soaked in oil and rabies that arguably have no idea what is going on.
You can tell by its blind, maddening shrieks that it has been given careful instructions.