People would like to secure their assets in times when there are crisis. Banks will be close so fiat would not be an option. During crisis, people would shift their wealth to something that would still have value even after the crisis and before they would buy more precious metals like gold or silver but since the existence of cryptocurrencies, some people prefer it because they can easily access it anywhere in the world giving them the freedom to have funds everywhere they go and without anyone knowing that they have it. An example would be in Venezuela. They are experiencing hyper inflation now that their fiat money is almost worthless and bitcoin or other altcoin give them an opportunity to have valuable money at times like this.