These datacenters are warehouses , filled with computers built for the sole purpose of mining Bitcoin. The financial markets are now onboarding bitcoin with considerations to add others. For example, the saying that bitcoin will go to zero. These wallets allow for quick and easy access to bitcoin, but the drawback is they put your money in the hands of a third-party company. There are only 21 million Bitcoin, and as time goes on, they become harder and harder to mine. Square is a huge financial technology company that includes many other services—one of which is trading bitcoin. If you are not cool with one or more of the 7 reasons, just stay away.