Cryptocurrency is a decentralized financial system with no middlemen and secured. Cryptocurrency are not only secured, but also are fast, transparent, anonymous and non-susceptible to government and central bank. As, cryptocurrency is decentralized there is less chance of inflation and also have lower transaction fees due to don't have any middle man. These kinds of features can attract people to Cryptocurrency market. And people losses their interest to use a bank. So, Banks fear about this.