A large drop in price, this drop is caused by someone with a mass amount of a particular coin who executes a “market sell” also known as sell until this "sucker" (coin) is sold.
The result of this is often dramatic, but fast, drop in price.
Drops ranging anywhere from 10-40%. This guy probably has been in the coin a long time and got it for way cheap or they just really want out.
In any case, you can grab all that they are selling and then sell it back over the next hour or two and grab X amount of profit with little effort other than buying the coin at flash sale prices.
The price typically bounces back because one guy with a “fat finger” like a "lead foot" someone who speeds was the only person who thought it should have been sold that cheap.
Everyone else still thinks it’s worth more, so the price bounces back.
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