It’s called Fall with good reason.
Less daylight means more night riding. Add leaf-covered, wet, slippery roots and rocks, and you have the increased potential for Falling.
But darkness makes me ride better. Not being able to see as well means that I can’t get picky with lines to take. It forces me to keep my body relaxed and moving forward.
If I ride a trail at night, and then ride that same trail during the day, I feel like I’m riding faster. Being alone in the woods, with an 8+ year-old light system and hearing Blair Witch noises also makes me ride faster.