People who are into cryptocurrencies will always tell you how great they are, because the only way they go up in price is when other people put their real assets into the pot. No actual value is ever created; no intrinsic value exists; and they're backed by exactly nothing, and quite literally, nobody.

Now, if it was simply an intermediary currency, fine (of course, stability and trust are key to any viable intermediary currency). But as an asset?!?! Insane!

You'll of course hear about "cryptomillionaires" and "cryptobillionaires", just like multi-level marketing schemes tout money-for-nothing rolling in. But you know where every.single.asset, every fancy house and car and plane (paid for in real currencies, natch) came from... from pulling money out of the "cryptocurrencies", essentially withdrawing money from all the "greater fools" still pouring their money in, who are (quite inarguably) seeking money for nothing (unlike work, to be sure, but also unlike legitimate investing, where you are, directly or indirectly, providing available capital enterprises that create actual value).

Ponzi schemes can defy gravity for quite some time, but when they pop... it's gone, all of it, immediate. NO INTRINSIC VALUE, just an empty bag. AND NOBODY TO BLAME, but yourself.

But oh, you better believe the high-profile cryptokings (and maybe even your chumpy crypto-touting neighbor, who already converted out most of his gains) won't be hurting, because where did all of that money go? It wasn't destroyed... it was just, uh, reallocated from suckers putting money in to those constantly pulling it out.

And when will these go pop? Like all bubbles, quite a bit later, longer than it might seem. Bubbles regularly continue to inflate long after they're widely recognized as such, up until the very last person who ever will say "man, I thought it was a bubble, but it just keeps going up and up and up, so I guess it's not a bubble, and I better get in." Once that last fool (the greatest fool, paradoxically, even though he might have managed to hold out longer than all the other fools who got suckered in earlier) puts his money into an overinflated (or in this case, fundamentally worthless) asset, it's like Wile Coyote, who has run off a cliff, then defies gravity for a while longer than seemingly possible... freefall.

Hope that helps. Creating value, however you can, is a glorious thing. Pure greed, and that's all this is, all the way around, is a sin that will only bring pain, at some point or other.