A stop won't help you on a trial failure because it will close one day at 5 and they'll announce the failure after hours and it will open at 2 and jump right over your stop (let's say you set it at 3.50).
But anyone who says you shouldn't set stops because of "bear raids" doesn't understand math. Being stopped out at 6 from the free fall from 8 a month ago would have allowed one to add 50% to their position for virtually free by buying back in at 4.
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