As for the why.......typical price action, really. Honey badger being a honey badger.
The Bakkt launch worked amazingly as a "sell the news" event. At the end of the day, it's impossible to predict exactly the form corrections will take. It would have been perfectly reasonable for the market to stay sideways in the $10,000s too. You only ever know in hindsight.
I still believe the downtrend since late June is just a correction to the bull trend. I'd be surprised if we weren't back above $10K by October.