As a lot of trading newcomers last days joining this community, I'd like to speak to you in a SEC manner: be careful, it still high risk investment. My question is: are you ready to global exchanges switch-off during the massive, universe dump?
Of course. Massive DDOS attacks targeting exchanges usually coincides with major downside volatility. Even without targeted attacks, the volatility of a blow-off top will probably cause trading engine malfunctions and exchange outages.
This causes inexperienced traders to mash the "market sell" button while orders aren't executing. When the orders finally execute, they've often sold the bottom.
I mean offline for a while, and then switch on again. Some of them would make it on purpose, some just wouldn't manage to deal with huge traffic.
We'll see more of this as the markets evolve. Regulated markets always have "circuit breakers" to mitigate volatility. For example, the CME and CBOE contracts have price controls that shut down trading once triggered.
It seems like Coinbase already has informal price controls.