coins have a client side wallet or we call it a coldwallet, which can be stored and secured by you only. You will have to do more research on how to secure currency of choice. The answer is out there if you seek.
I do understand how the value of cryptocurrencies is formed but I was looking for an explanation why e.g. BTC is safe. Almost nothing can happen to gold, so its value will always remain (we're not talking about conditions when it can loose its inner value, like shrinking of spheres of application). So what preserves BTC from a collapse? Since it has no inner value.
Limited supply and supply/demand rule
The use of energy: currently blockchain uses large quantities of energy to ensure its security. Price factors appear here because it takes a certain amount of energy on average to ' mine' a Bitcoin. The value of the goods is determined by evaluating the cost of labor.
bitcoin has value Exchange