At 21, you can live life with reckless abandon, as reckless as your abandon is. Then, at 30, there's something there are the supposed to be's. You're like, "I'm supposed to be doing this. I'm supposed to be doing that." You start measuring your life by what you think you're supposed to be doing. Having recently turned 40, it's like, "What the hell?! Why am I worried about what I'm supposed to be doing? What do I want to do?" You become fine with wherever the road takes you.