Secure, Transparent, Immutable
Even the most secure centralized database, stored at the servers of a trusted organization, such as bank, can be hacked and the information will be lost or forged. To alter any data in the distributed ledger, you have to change every existing copy of the cryptographically protected blockchain, which is next to impossible.
Blockchain is transparent and immutable, which means that every transaction, validated by all network members, remains in the blockchain forever. Any changes in the chain are visible to all system members immediately and there is no way to delete or re-write any transactions in an attempt of fraud or forgery.