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 previous answers make valid points regarding the risks, and why you can't reasonably compare trading for profit/loss to a roll of the die. This answer looks at the math instead. Your assumption: I have an equal probability to make a profit or a loss. Is incorrect, for the reasons stated in other answers. However, the answer to your question: Can I also assume that probabilistically speaking, a trader cannot do worst than random? Is "yes". But only because the question is flawed. Consequently it's throwing people in all directions with their answers. But quite simply, in a truly random environment the worst case scenario, no matter how improbable, is that you lose over and over again until you have nothing left. This can happen in sequential rolls of the dice AND in trading securities/bonds/whatever. You could guess wrong for every roll of the die AND all of your stock picks could become worthless. Both outcomes result in $0 (assuming you do not gamble with credit). Tell me, which $0 is "worse"? Given the infinite number of plays that "random" implies, the chance of losing your entire bankroll exists in both scenarios, and that is enough by itself to make neither option "worse" than the other. Of course, the opposite is also true. You could only pick winners, with an unlimited upside potential, but again that could happen with either dice rolls or stock picks. It's just highly improbable. my chances cannot be worse than random and if my trading system has an edge that is greater than the percentage of the transaction that is transaction cost, then I am probabilistically likely to make a profit? Nope. This is where it all falls apart. Just because your chances of losing it all are similarly improbable, does not make you more likely to win with one method or the other. Regression to the mean, when given infinite, truly random outcomes, makes it impossible to "have an edge". Also, "probabilistically" isn't a word, but "probably" is.