Arbitrage losses of several million dollars—most people can't handle the psychological pressure as well as those doing contracts. People trading contracts can face massive drawdowns, liquidation, and losses, cry for an hour, then pull themselves together and go all-in again. But with arbitrage, you're earning 0.5% daily, watching your profit curve steadily climb at a 45-degree angle over six months to a year. Then, one big red candle wipes it all out because risk control wasn't done properly. After something like that, you'd probably be in shock for days. Oh, and it's like those doing grid or martingale strategies, thinking they're super smart and risk-free, not needing to make subjective judgments about price action—just profiting off the volatility. Then one extreme market move wipes out everything. These arbitrage losses are often the ones that hurt the most.