NEO recently had a flash crash to just $3 on Bitfinex, down from $32.50 when it crashed. The reason for this crash was a massive whale dumping it down, causing stop loss sell orders to be triggered, as well as many actively watching the price to panic sell. It did not remain at $3 for very long, as the sell orders were quickly bought up, bringing it quickly back up to the low 30's in price.
The person or people who made this power play are probably either dumping their holdings due to insider information, or looking to drive the price down to accumulate. If you had shorted NEO you would have been wiped out as well. This flash crash, however, did not happen on other exchanges. It is my belief that bitfinex is one of the worst exchanges that you can use to trade altcoins. Due to the ongoing Tether scandal, as well as the fact that many were completely wiped out on Bitfinex today, I would not trust it with any significant amount of money. I have good reason to believe they are insolvent, and if everyone tried to withdraw their money, they would soon run into a big problem.
Sources: Bitfinex.com
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