To my way of thinking, the fact that life showed up on Earth relatively quickly, within half a billion years of the planet's formation, suggests that life is relatively easy. The fact that complex life took another few billion years after that suggests that simple to complex is the difficult step. But the fact that we nonetheless find ourselves here around a live-fast-die-young yellow star when the universe is only 14 billion years old rather than in close orbit around a dim red star a hundred billion years later suggests to me that it's probably not a one-in-every-zillion universes sort of event.