I watched Bitcoin plummet, in August I think it was, to below 1,400GBP from around the 2,500GBP mark. Alas, I couldn't get on board at that time for two reasons ... Coinbase would only allow me a weekly debit card limit of 350GBP (I'm allowed 2,500GBP now) and during that price drop I had about 30GBP
left to spend in my Coinbase account.
The other reason was that the Coinbase site suddenly shut down for "maintenance" purposes! It always does this whenever there's a big price drop in Bitcoin, it happens so regularly that it cannot be pure coincidence. Their (Coinbase's) customer service is absolutely appalling! If anyone's in any doubt about the shocking way they treat their customers then just Google "Coinbase Customer Service reviews.
If the cryptocurrency market were regulated then Coinbase would be shut down - it's this complete lack of faith in them that prompted me to move my Ethereum onto my Nano Leger S. I would advise anyone thinking of buying cryptocurrencies to get some form of cold storage and don't leave the keys to your coins on the exchanges.
The biggest Bitcoin exchange in the world at the time "Mt. Gox" got hacked twice and lost over $460 million of customers' Bitcoins.
https://www.wired.com/2014/03/bitcoin-exchange/
In fact, very few exchanges have escaped the hackers.