That's only true if you leave your money in...which you don't have to do.

You can play prediction markets by betting on a swing. E.g. I made a few hundred dollars betting on Harris in 2024 when Trump was at ~65% odds and then selling before the election when it was closer to 50%.

▲

JumpCrisscross 4 hours ago | parent | next [-]

> can play prediction markets by betting on a swing

The outcomes are still capped. In that respect, it's more like a derivative market than the stock market. You can trade in and out of options. But the value in the system is tightly defined and, after fees, a net negative-sum game.

▲

kqr 3 hours ago | parent [-]

There are no fees on Polymarket. Not sure about others.

	▲	JumpCrisscross 2 hours ago \| parent \| next [-]
		> There are no fees on Polymarket "Currently, small fees apply to Crypto and Sports markets. Starting March 30, 2026, this will expand to include other categories like Finance, Politics, Economics, Culture, Weather, and Tech" [1]. More critically, Polymarket doesn't pay interest on deposits. (Kalshi does.) [1] https://help.polymarket.com/en/articles/13364478-trading-fee...
	▲	barchar 2 hours ago \| parent \| prev \| next [-]
		There is a fee implicit in the market spread. It's formed out of the time value of money w.r.t. the cost of NOT trading as well as the adverse selection faced by those with standing offers. Increased insider trading will increase spreads.
	▲	kasey_junk 2 hours ago \| parent \| prev \| next [-]
		Depends on the event: https://docs.polymarket.com/trading/fees
	▲	2 hours ago \| parent \| prev [-]
		[deleted]

▲

barchar 2 hours ago | parent | prev [-]

In that case you limit your upside as well as an insider, and have to deal with liquidity and slippage coming and going.