Because life, more often than not, would surprise you in a funny way. Of your dreams come true, or of your day turn sour. This might be written in the star, but also might fall out of nowhere.
That after today, my life will not be the same again, it is time for another chapter in life, I believe. Like lessons in books or chapter in a play, each chapter has different difficulties and scenes. Each you want to absorb, pass or ponder upon. But each lesson in life, it has the purpose to upgrade your self.