Candidly, you might not. If you don’t have anything of value whatsoever, not a car, not a bank account, not a dime to your name, you may not need an estate plan.
However, if you have any assets of value, you can direct where those things go. And you may want them to go to your children, you may want them to go to your grandchildren or charities or religious organizations. Without having an estate plan in place.
You don’t get to make that decision. The state will make that decision for you. And frankly, they make decisions that that most people would not choose for themselves. So if you have things and you want to make sure you can decide where they go, you probably do need an estate plan.