Because they want to see other people suffer

They get manipulated about and distracted by certain issues. The people who want power know this and exploit topics such as guns, abortion, fear of crime, racism/nationalism, sexism, economic issues and taxes. Plenty of people vote republican because they have been convinced that Democrats will take their guns, allow in too many immigrants (with the implicit idea that immigrants are bad somehow), be worse on the economy, raise taxes, let criminals get off easy, reduce the influence of Christianity, and so forth.

There’s also the decades of propaganda about socialism and communism, and against social safety nets as well as government and anything run by the government vs a private entity. So basically, because they’re not very aware or well informed and all themselves to be convinced by propaganda.

They're idiots

Do we actually vote to benefit the rich?

Many vote for leaders that openly cater to the rich, but I don’t know that we actually consciously vote to deliberately help the rich.

Those elected people are the ones telling everyone that the rich are the job creators. They used to feed us the farce that trickle-down was viable, they don’t even bother with the lie anymore. The rich are just squatters on wealth. They get that wealth by consolidating businesses, hoarding assets like real estate, creating artificial scarcity, enshittifying everything, and squeezing labor for more productivity while expending massive effort to minimize overall compensation.

And they own the media. All of it. Even the “liberal” media is mealy at best about taxing wealth or anything critical of the uber-wealthy, anything right of center is openly against tax, particularly of anyone with wealth, making the wealthy the “victims” of the left’s ideas while the wealthy are just parasites victimizing us all.

All that aside, the real crux of the issue is identity politics. Being a sycophant of the rich is no longer any different than being a evangelical supply-side Jesus CINO, pro-gun, anti-government, anti-tax, anti-environmental regs, blah blah and all the rest of the mulish conservative BS.

They don’t actually care if we cater to the rich. They care that their team says we should bend over and give the rich everything. Just like their team says school shootings are an acceptable price for having your own personal arsenal, or spreading a potentially deadly disease is better than being inconvenienced by closed restaurants.

Obstinate tribalism has gleefully supplanted critical thought.

Who is there to vote for otherwise? Two sides of the same coin. The rich try to keep politics about anything except wealth inequality. The rich keep the good candidates off your ballot long before it’s time to choose between tweedle Dee and tweedle dum.

I think that it depends on the person. I've heard of enough people who voted for Donald because they like that he "says it like it is", or "he's a businessman", or because they just want lower taxes. Some people are so exposed to rage-bait social media/news content and are always being told what to be afraid of and they vote emotionally based on that fear. My grandfather votes the way he does because he's TERRIFIED of immigrants, even legal ones - because all he does is sit and watch fox news. I think most often, people are busy with their lives, paying their bills, taking care of their kids, etc. and don't have a lot of energy left over for politics. People treat voting like it's team sports. A ton of people voted for Donald because they thought tariffs were paid by the other country, not American businesses. I don't exactly blame people, it's a lot of information and life is probably a lot more relaxed for people that don't follow it.

Stupidity, cult mentality, “my sports team” mentality, religion, and single issue voters.

Usually this happens when you dont have a democracy. Establish a system with rank choice voting and a few dozen candidates, and you'll see votes closer aligned with voter interests

The majority of people vote with their gut and won't look deep into what politician A is promising, so long as one of the promises is exactly the thing the person wants. For a considerable number of gamers, it's dealing with woke culture. Trump is a fervent enemy of "the woke", but he also promised hefty import tariffs on everything, so consoles can get really damn expensive. But hey, the woke sjw's are getting owned!!

This piece on Aftermath touches an important point as well, that left leaning content often takes care to not spout random bullshit, while right leaning will just say whatever because haha engagement goes brrrrrrr.

Going off a tangent, the Brazilian right complains that "the poor vote with their bellies", implying they'll vote for whoever promises "free money" or "free meals", usually in the form of govt programs. During election years, the right will try to claim they were the masterminds behind every sort of program meant to help poor people, such as Bolsa Familia, while loudly and constantly complaining about their existence and doing everything in their power to block money outside election years. It's common to find people who depend(ed) on Bolsa Familia to survive that complain about "freeloaders" that "want to be fed by the government". A good portion of right-wingers also believe that the govt pays a whole minimum wage to every person in jail, despite this bullshit being debunked several times already.

One's "own best interest" can take a lot of different forms. Especially when the number and variety of plausible candidates are finite. Your preferred candidate for a given office will rarely line up perfectly with your own values. There's a compromise there.

If I vote for my own finances, it may come at the cost of my morals. It I vote for my own moral interest, it may cost me more. If I vote for my own power, it may cost someone else their freedoms. How heavily do I weight my own interests against those of a wider society? Political identities and philosophies are complicated, and can't necessarily be reduced to a single binary choice that is "best" in every scenario.

Most are wanting an end to this current system so they’ll ‘play’ it out knowing albeit the struggle, Democracy has left the building and late stage capitalism is showing the disparity of the predators and preys of society

If I’m struggling this much now then imagine how much harder it will be when I have to pay higher taxes

The rich are clever and very well coordinated

Because it's no longer about benefits or interests.

It's about the "my side won, your side lost, get over it" mentality. It's about the tribalism and making sure you keep your ire focused on your fellow man rather than looking up and seeing the source of your problems

And it's not just the US. It's fucking everywhere.

They believe it will benefit them one day.

In the US, is this actually the moment past the point of no return? Would you ever allow yourself to accept that truth if so, or will you need to see actually bodies in the streets before you believe it's over?

False consciousness.

Because everyone thinks of themselves as a potential rich person. Or in other words: people think that being rich is the ideal state, so let’s align everything around that.

If we truly put a yoke on the rich and contained them, we would also be reining in the smallfolks dreams.

By contrast, rich people don’t sit around dreaming about being smallfolk and planning aspirationally for the day that will happen.

Kind of an indirect answer, but I've heard people state that they vote against their own personal beliefs because they think that there needs to be a balance between "good and bad". Obviously, this is complete bullshit. Even if there should be a "balance", we already have enough problems as is, we don't need the government making it worse.