no, someone to make decisions--medical and otherwise--for you if you are medically incapacitated or otherwise non-decisional. doesn't have to be a spouse/partner, could be family.
I dont have family beyond my parents so once they pass it'd either be a wife, one of my scumbag friends, or maybe an attorney.
Well, that's what Power of Attorney is, but there are variations of it. I've given that to my father currently, but once he dies it will go to my best friend, whom i've known since i was six years old and i trust with absolutely everything.
I don't have much cash, but i do own quite a bit of property, so i have that all broken down as to whom it goes to if/when i die.
I update the estate/will every few years.
I've also had my GF added into it for a small sum of money, granted she signs an agreement; which we haven't completed. I'm not going to leave her out, but she sure as hell isn't getting half my shit. We have agreed to never get married nor have children, and since i can't have children without a medical procedure, that's an easy thing to negotiate.
My brother in law worked as a divorce attorney for 12 years and has told me all the loopholes to avoid having to give up anything to my GF. It's not because i'm an asshole, it's because i've worked my ass off to be successful and my GF has not contributed to that at all. IF we had children, obviously that would change, but i don't plan on it. She's like my best friend and amazing sex partner, travel buddy and chef all in one.

If kids are removed from the equation, i don't think anyone has rights to my money or property. To see over half my friends get buttfucked by their ex-wife has left me a little salty, but for obvious reasons.