It's currency speculation, one of the most notoriously dangerous things to invest in. It's also completely unregulated and so no organization will be able to halt trading if it crashes 70% ... it will just keep going.

Also for every bitcoin millionaire there's countless people like me who didn't buy and sell at the right time. You see it go up 10%, you have no idea what's going to happen tomorrow, so you say "oh, this is a fine roi." Trusting the market has ruined many more fortunes than it's made and greed is rarely a bearer of good luck.

And finally, trading is like coming up with passwords. You may think you're clever but in reality, your innovative strategy was likely programmed as an algorithm 30 years ago and your perceived edge is likely imaginary. TA bots, arbitrage systems, pump-and-dump commenting botnets, and sentiment analysis of big-data for leading indicators have been used by traders heavily since, well, the beginning - remember where bitcoin came from; everyone who had a coin in 2009, before you ever heard of btc, was likely also savvy enough to leverage all of these.

Also, Do Not Keep Too Much In Exchanges. If history has taught us anything, it's private wallets on private computers that are turned off most of the time is the safest place to store them. If I was a criminal with a 0-day exploit, the very first thing my code would do on a victim's computer is look for wallet.dat.

So have fun, trust nobody, don't panic, and it's probably best not to invest too deep.

This type of prediction comments always strikes me as nonsense and containing zero actual information. If you believe this, either post fundamental analysis that argues your case and have the hope of providing some valuable insight, or - even better - put your money where your mouth is.

The same thing happened when people claimed to be 99.999% sure Trump would never be president, but of course they never actually bet any money on it.

One could argue the grandparent doesn't argue their point either, but they definitely seem to put their money where their mouth is. All these people who are so against crypto and like to sit at the sidelines moaning about a bubble, why don't you either short it or bet against it? A la http://blog.samaltman.com/bubble-talk

You can be right that it will crash and still lose your shirt if you short it, if you are wrong about the timing. As Keynes said: “the market can stay irrational longer than you can stay solvent.”

There is an inherent asymmetry between going long and short. If you're going long, your losses are capped at what you put in, and your gains are unlimited. The opposite is true if you are going short: your losses are unlimited, but your gains are limited.

That's a good counter argument, thank you. This is why I also mentioned betting against over a multi-year period, which you can do manually like Sam Altman did with tech valuations, or using something like longbets.org. You can also structure the bets so your losses or gains are limited or unlimited on whatever side you want, assuming you find a counterparty who is willing to take the bet.

It is definitely more work though and maybe not something most people are willing to do unless they have strong reasons to believe they are right and can profit from it.

(Another way is also to do proxy bets/investments, i.e. go long on things that are inversely correlated with X, but this is less practical in the case of cryptocurrencies for various reasons.)

You don't have to sell short, you can buy puts which give you far greater (not unlimited) upside than your capped downside.

True, but then your timing is even more crucial. You can be right about a coming crash, but if it happens after your put option expires, it won't do you any good...

My money is staying away from the volitility of crypto currency.

It's very hard to predict this market in the long and the short term. As far as I can tell speculation is the only driving factor in bitcoin. Not something I want to bet on or against it's too random for me.

it crashed many times and recovered in each instance. Overshoots and volatility are part of owning it . But given how much money is at stake now, I predict the crashes will become smaller. if someone or some firm is buying $100-200 million of bitcoin they are not going to sell it on a whim.

He no doubt rebalances his portfolio as things change. It's not free money.