One day, when you wake up and realize that your 20s suddenly disappears, then welcome you to the 30s. A dream like a prince riding a white horse coming to pick you up and then happens a dream marriage; or a dream of starting a successful business and become rich, would be no longer a dream, they could be real thing in life. That is not necessarily a bad thing, but you perception would be more accurate when we come to 30's. Of course, at this age, the concept of "happiness" is no longer something that is in the sky, it will be very practical.
It is important for us to give our own definition of "a happy life" so that we can look at our lives in the most honest way. By the age of 30, that honest vision will make our path to happiness ever closer.
Unlike the 20s of daring and impulsive, the 30s has the ability to calmly observe ourselves and the world, understand ourselves and our strengths; and surely, there will be a time when we remember about our 30s as "the 10 most exciting years of our lives".