Hawaii Doesn't Spring Forward or Fall Back

Why does Hawaii not observe daylight savings time?

It's due to Hawaii's location. First, Hawaii is so far south (i.e., close to the equator) that there's little change in the time between sunset and sunrise throughout the year - there's not much more daylight in June than there is in December. Also, Hawaii is close to the western boundary of its timezone, which means everything already happens later by default, both sunrise and sunset. Keeping this in mind, even in June the sun rises rather late, and if there were DST in Hawaii the sun would rise just before 7 AM, which is pretty late. Thus the gain in evening sunlight is cancelled for many residents by a loss in morning sunlight, hence the state of  Hawaii decided not to participate in daylight saving time.