The habitable zone of a star ('Goldilocks Zone') is determined by the size and temperature of the star. A planet too close will be too hot for life; those beyond the zone too cold.
The Grand Design
The laws of nature seem mysteriously crafted to allow for complex life. Scientific explanations involve the existence of multiple universes with different sets of laws. Thus, a universe with our set of laws is no more special than the unique configuration of our solar system or the very planet we live on.