As a general rule during the day you are more inclined to be at work so a more professional, less provocative fragrance is called for. In the evening you are more likely engaged in romantic adventures so something romantic and attention grabbing.
Think of the difference in how you dress to go to work vs how you dress to go out on a date and apply these same rules to your fragrance choices.
Take a look at the Basenotes awards. They have categories for Day wear and Evening Wear to get an idea of what fragrances fall into what category: