Offer your thoughts or opinion on the input financial query or topic using your financial background.

Is it accurate to say that if I was to trade something, my probability of success can't be worse than random?
The stock market is not a zero-sum game.  Some parts are (forex, some option trading), but plain old stock trading is not zero sum. That is to say, if you were to invest "at random", you would on average make money.  That's because the market as a whole makes money - it goes up over time (6-10% annually, averaged over time).  That's because you're not just gambling when you buy a stock; you're actually contributing money to a company (directly or indirectly), which it uses to fund activities that (on average) make money.  When you buy Caterpillar stock, you're indirectly funding Caterpillar building tractors, which they then sell for a profit, and thus your stock appreciates in value.  While not every company makes a profit, and thus not every stock appreciates in true value, the average one does. To some extent, buying index funds is pretty close to "investing at random".  It has a far lower risk quotient, of course, since you're not buying a few stocks at random but instead are buying all stocks in an index; but buying stocks from the S&P 500 at random would on average give the same return as VOO (with way more volatility). So for one, you definitely could do worse than 50/50; if you simply sold the market short (sold random stocks short), you would lose money over time on average, above and beyond the transaction cost, since the market will go up over time on average. Secondly, there is the consideration of limited and unlimited gains or losses. Some trades, specifically some option trades, have limited potential gains, and unlimited potential losses. Take for example, a simple call option.  If you sell a naked call option - meaning you sell a call option but don't own the stock - for $100, at a strike price of $20, for 100 shares, you make money as long as the price of that stock is under $21.  You have a potential to make $100, because that's what you sold it for; if the price is under $20, it's not exercised, and you just get that $100, free.   But, on the other hand, if the stock goes up, you could potentially be out any amount of money.  If the stock trades at $24, you're out $400-100 = $300, right?  (Plus transaction costs.)   But what if it trades at $60?  Or $100?  Or $10000?  You're still out 100 * that amount, so in the latter case, $1 million.  It's not likely to trade at that point, but it could. If you were to trade "at random", you'd probably run into one of those types of situations.  That's because there are lots of potential trades out there that nobody expects anyone to take - but that doesn't mean that people wouldn't be happy to take your money if you offered it to them.   That's the reason your 16.66 vs 83.33 argument is faulty:  you're absolutely right that if there were a consistently losing line, that the consistently winning line would exist, but that requires someone that is willing to take the losing line.  Trades require two actors, one on each side; if you're willing to be the patsy, there's always someone happy to take advantage of you, but you might not get a patsy.