Astrophysicist Hugh Ross writes:
My answer: I get asked this question nearly every time I speak on a university or college campus. Apparently, the hypothesis that humans became compatible or naturally evolved to adapt to Earth’s present conditions has become dogma in many university course offerings, more so in the social sciences than in the physical or life sciences. Consequently, I devoted an entire book to answering this question, Improbable Planet.1 Additional evidences that our supergalaxy cluster, our galaxy cluster, our galaxy group, our galaxy, the Local Bubble, the Local Fluff, the solar system, and the Sun, Moon, and Earth have been exquisitely prepared and designed for humans are presented in my next book, Designed to the Core.2
A very brief answer is that the Milky Way Galaxy, the solar system, and Earth were designed to be the ideal home for humanity and global human civilization millions and billions of years before humans showed up. More than 400 distinct features of Earth must be fine-tuned to make our existence and civilization possible.3 Even with all this exquisite fine-tuning the time window during which humans can exist in a civilized state is extremely narrow.4 It is no random accident that we happen to be here during this narrow time window when the resources we need to sustain global civilization are uniquely available.