While viable, it's incredibly unlikely that Bitcoin will be hacked — in part due to the fact it's built on the Blockchain, which is constantly updated, maintained and reviewed by Bitcoin users. But that's not to mean it's entirely safe.
Just like a bank account can be compromised, Bitcoin Exchanges and Bitcoin Wallets can both be hacked into and their balances drained. This is why it's imperative you possibly can to protect your Wallet, by switching to a Cold Wallet and/or enabling 2FA.
What is 2FA?
2FA — short for Two-Factor Authentication — is an additional layer of security to protect an account or a system, requiring users to enter an additional password, PIN, fingerprint, hardware token or another method of authentication before they're able to log in.
Password + Additional Authentication Barrier = 2FA