Why does the Master of the Scales want to bring balance between the good and evil that's measured by his scales, not to have the good conquer the world? Because if the Fridge Horror theory that it'd result in an endless daytime is correct, the life that is dependent on darkness will suffer. Nocturnal creatures aren't any less important than diurnal creatures.
It's never discussed what would happen if the good measured by the Master's scales outweighs the evil. Would that result in an endless daytime, just like the evil weighting too much in the scales results in an eternal darkness? If the sunlight never leaves for a time, life will suffer as it does from sunlight's complete absence, especially the nocturnal animals.
