Bitcoin can be stolen. Although “Bitcoin” can’t be hacked, it’s only software and has many vulnerabilities. If held on an exchange, you have legal and financial risk. If held at home, you could have a hard drive fail and lose your passwords. If it’s on a hardware fob like a Trezor, the circuits could fail. For a robust system, computers themselves are pretty fragile. You could write down your passwords on paper, and have a house fire. You could print out several copies, but if any of the copies are found, they have full access to your account and stolen without you knowing. You could have your passwords stolen by your family, or have a trojan take a screen or keystroke capture.
Hackers could find a vulnerability not in Bitcoin, but in Android or AppleOS, slowly load the virus on 10,000 devices, then steal 10,000 passwords and clear 10,000 accounts in an hour. There are so many things that can go wrong, not because of the software, but at the point where you interface with the software. Every vault has a door. The door is what makes a vault useful, but is also the vault’s weakness. This is no different than leaving blank checks around, losing your debit card, or leaving cash on your dashboard, but it’s not true that there are no drawbacks. However the risks are less obvious and more unfamiliar.
http://www.zerohedge.com/news/2017-12-10/crypto-cornucopia-part-5-well-be-lucky-survive-our-own
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