Or we go through a brief period of hardship as with any transitional phase in history, and allow automation to become so prevalent that the average person won't need capital to purchase goods. Eventually, if we allow it, we will be able to create machines that can produce just about anything we could want with zero input from humans. Even maintenance, programming, and production of the machines can be handled by other machines. And since we won't have to pay the machines to do all this work for us, that means the cost of goods will effectively drop to zero. After all, machines don't have profit motive.
Sounds like a horrendous crossover between Star Trek: The Next Generation, the Terminator movies, and the conditions that led to the Butlerian Jihad in
Dune (the real series, not the KJA/BH stuff).
So while the machines are doing everything, what are the humans doing? And at what point do the machines decide the humans are an infestation and decide to exterminate us?
I'm talking about a world in which machines run and produce everything so there is no longer a need for any type of currency to exist. How is that individual profit?
Unless humans go through some kind of fundamental and lasting change in our thinking - not just intellectually, but at gut level - there will always be some kind of currency. It's really annoying how people keep saying there's no money in Star Trek. There certainly is, if you understand that one careless line in a movie really meant that Starfleet, and the major worlds of the Federation don't use
cash. But no advanced society can function without some kind of economy. Even on Voyager, cut off from Federation services, developed an internal ship's economy, where the currencies were replicator rations and holodeck time. They did a lot of old-fashioned bartering, too.
So considering that machines do most of the heavy work in that setting... and they still not only have an economy, but some regional currencies (gold-pressed latinum is the one used by pretty much everyone on Deep Space Nine, even by the Federation citizens stationed there)... currency really isn't something it would be so easy to get rid of.
Nor do I. If it is brutal though, I suspect it would be the Luddites that would make it so by resisting the transition.
I'm someone who tends to resist adopting new technologies until I really need it. Only the demise of my beloved Smith-Corona electric typewriter (I used it so much, it literally wore out past fixing) got me to try computers. Even so, it was still 14 years after that when I finally got an internet connection at home.
I don't consider myself a "Luddite". I just consider myself someone who uses the technology that works for the job that needs doing, at a level with which I'm comfortable. Of course that's not to say that if someone were to perfect the holodeck, that I wouldn't enjoy programs of my favorite books or TV shows, or spend time in a favorite vacation spot.
"It is by will alone I set my mind in motion" would be an optimistic outcome.

Mentats are thought of as "human computers" - a necessary adaptation in the wake of the Butlerian Jihad that did away with anything resembling AI.
That's a line from the Lynch movie, but I don't recall it being in the actual Dune novel.
I think it's pretty obvious and I've already said it several times. If machines run everything and produce everything, then production costs drop to zero. Machines also have no profit motive, so it's not like they are going to charge us a price for the goods and services they provide. So with everything freely available, there is no longer any need for currency.
Also, when I say machines will run everything, I mean everything. They will be the owners and operators of all the corporations, and they will be the governing body for every nation. Basically, all humans would have to do in this world that I envision is exist. Beyond that, people would be free to do whatever they damn well please as long as it doesn't infringe on the rights of others.
Exist and do what? You're describing a dystopia I would never want to live in. What would machines know of the human connection to nature?
How much do you really care that the thing you order from in a fast food joint is a person?
I'd prefer a person. You can talk to people if there's a question that needs asking. That's the same reason I prefer to be served by a real person in the bank.