true plenty of times or case happen that banks are being close...one of the banks here in my country is being closed and my parents put their savings there bad happen that it was close because of being bankrupt and until now they did not refund my parents..sometimes it is really hard to trust even big names of banks.
I think banks are guided by the respected policies of every country. They are protected and guided by law for the protection of it's depositors therfore there' s no reason we should not trust banks. However, like any other establishment or business there is always rooms for risk and failure just like in saving bitcoin to our wallets. All we have to do is to be vigilant and wise in our decision making.