There are plenty of reasons organisms die other than aging. Accidental death as being cited here is certainly one, but also predation, disease, and intentional

There are plenty of reasons organisms die other than aging. Accidental death as being cited here is certainly one, but also predation, disease, and intentional killing or maiming that leads to death from other organisms competing for the same resources, whether that be humans waging war, male oxen fighting for breeding rights, lions killing hyenas and cheetahs to maintain dominance over hunting territory, or plants that strangle out other plants to hoard scarce sunlight. There are also plenty of animals that more or less die on purpose to make way for the next generation. A fair number of insects are designed to only ever go through one breeding cycle, including some that don't even have mouths because they come into adult form with the energy they need to reproduce and no more and that's all they'll ever get. The giant octopus spends a season fattening up so she can stay in the nest tending to her clutch while all of her eggs mature, never leaving and starving to death as she does so. Life on the larger scale depends upon individuals themselves continually being born and dying to maintain the level of dynamic adaptability that allows life to flourish as local ecosystems and the planet at large change. A programmed maximum lifespan via aging is only one of many ways that happens.