Trading is similar to gambling in a casino in that you are taking a risk to make monies. However, in a casino, the odds are fixed in favor of the casino and you are guaranteed to lose over time. In the stockmarket, you are taking a risk but, your risk can be controlled thru risk management and on top of that, you can put the odds of making monies highly in your favor. If each time you lose, you lose $100 but, each time you win, you win $700, what are the odds you will make monies assuming you have a 30% win rate only. That means you lose 7 times out of 10 trades. So you lose 7 times x $100 = $700, you win 3 times x $700 = $2100 for a net gain of $1,400. Nobody is forcing you to place trades and you can always be very selective and only trade when the reward is several multiples of your risk.
Except in trading the odds of a given event occurring are never known with fixed certainty. Whereas in gambling they are fixed and known (largely.) Vanilla option delta is about the closest we can get to fixed odds, and even then it is only an approximation.
I'm not familiar with other derivatives like barrier options and knockouts, but I doubt they have fixed and known odds either.
