I'm more comfortable riding at night than I am during the day. My headlights produce 500-750 actual lumens (1000-1500 lumens if one is to believe the manufacturers), so I can see road debris, bike ninjas, low hanging branches, etc. pretty well. Further, bright bike lights (at night) provide greater contrast with my surroundings than my bike and clothing can provide during the day, so I'm more visible to other road users. Traffic is usually lighter after dark than it is during daylight hours (though less so during the winter), which is nice. Riding at night offers visual cues (from headlights) in addition to aural cues regarding traffic approaching from directions I cannot readily see. These cues are generally only available audibly during the day.