All investments must have a risky opportunity. Both in banks and in bitcoins. On bitcoin, we can control full of our bitcoin.When you choose the high risk there is a chance to lose or gain 100% of your investment (Medium is 75% and low is 50% if I remember it right). But bitcoin is much more profitable ten times than the bank and its decentralized.It's a bit of a picture of me so you alone can choose the best for you. If I personally, I will balance the investment in the bank and on bitcoin.
I personally do not think that there is any such risk in bitcoin or banking system. Although trading risk is always there in every king of trading and investment. But if we have some good experience and remain careful then we can reduce the risk of long money in trading.