Know your exact risk. With binary options, you always know your exact risk and profit before you enter the trade. With forex, even with a stop loss, you can get hit by slippage when the market moves quickly such as on a major news event or economic data and your stop might not get filled at the price you want.
No additional transaction costs. Transaction costs are factored in to the payout, so there are no additional costs, In spot forex, there is the spread which can widen at certain times and sometimes commission too, depending on your broker.
No stop loss to get hit. How many times in trading regular forex has your stop loss been hit before the trade turns around and does exactly what you thought it would. Well with binaries as there’s no stop loss to set, in these situations, you would still be in the trade. As long as you are above (or below) the level you set at the expiry time even if it’s just by a tenth of a pip, you will still win.
Less complicated. When entering a trade there’s much less chance of errors. There’s no working out of pip values and stop loss setting, and no need to manage the trade, so no adjusting of targets or stop levels
No trading on margin. In forex you can use leverage sometimes up to 500:1, so there can be big winners but also big losers. In binaries, you don’t use marging. There’s still the potential to make high profits, often 90% but you will never get a margin call.