Cryptocurrencies are used for speculation because they are extremely volatile and give an opportunity to earn money. Now traders are actively using cryptocurrencies to earn money and to trade.
Cryptocurrencies are used not only for speculation, but also for investment purposes. Especially for investment purposes, diflationary coins are popular, whose issue is limited and the total number decreases over time.
Cryptocurrencies are showing good growth, deflationary coins with a limited supply are especially popular now. People buy deflationary coins in the hope of their further growth due to the limited supply.