Stop Losses & Max Pain — Where the crowd gets blown up
Max pain is the price where the most option contracts expire worthless. Say SPY's at $560 on Friday morning and max pain for that week is $555—market makers and big money who sold those options would love to see SPY close right there, because calls above $555 and puts below $555 all die worthless and they keep every dollar of premium.
The crowd gets cooked when they chase momentum into expiration without watching where max pain sits. You buy 0DTE calls at $562 because SPY's ripping, but if max pain's at $555 and there's no real catalyst to push through, the tape can just bleed sideways or fade into the close. Theta eats you, volatility drops, and by 4 p.m. your calls are toast even though you weren't technically wrong on direction.
Stop losses help, but they're not magic in options. A 50% stop on a $2 contract means you're out at $1—but if the bid-ask is wide or volume dries up into the close, you might not get filled until it's worse. The real edge is position sizing and asking whether max pain or a key level is sitting between you and profit before you even enter.