Dogs are bred to live with humans. Tigers are not.
Same thing has been done with servals ("savannah cat"); I can only imagine how awesome/terrifying it would be with other lesser wild cats, although I think there are enough differences between the great cats and domestic cats to make it difficult/impossible to do naturally (tiger/cat or leopard/cat cross).
So, I think there is a hook. It's just a really shitty one. Note that the hook for dogs can backfire as well, if they try to assert pack dominance vs. their owner. So we breed really submissive dogs.
Tigers and lions are very confident apex predators, so they don't really have the vicious instinct or the intense fear response that some animals have. So they don't deliberately attack humans. By contrast, leopards and jaguars will kill you out of sheer viciousness, bears will attack you if they feel threatened, and polar bears will attack you because they are hungry and you are made of meat.
The main danger with tigers and lions is that they don't really understand how fragile humans are, so they might accidentally kill or maim you, which happened to Roy.