While the government might claim that you're an adult once you turn 18, anyone who's ever met an 18-year-old knows that couldn't be further from the truth. 18-year-olds might act like they know everything in their Introduction to Western Civilization lectures, but their independence is relatively underdeveloped. And you know what, that's okay! I'm not saying it's great to live in perpetual adolescence until you're 40, but 18-22 function well as ages to practice adult independence without bearing the full responsibility of caring for yourself in every regard. You might work full-time but live at home or live in a dorm at college but rely upon your parents financially. You can't expect a teenager to leave high school and immediately be able to provide for themselves in every regard. While some kids do that, it's usually because they don't have a family to support them, like the young woman who went viral for her mom kicking her out months after her high school graduation.