A tiger’s purpose in life is to hunt, fight, and hopefully kill game animals.
A male lion’s purpose in life is to intimidate, fight, and if necessary kill, other predators, including large cats.
Don’t be fooled by the fact that the lionesses hunt. In every mammalian species, the male assumes the high-risk tasks (because males are more expendable). In lions, hunting is relatively low risk, but fighting off competition is high-risk.