Can be used safely, but I think it depends on the users. The system itself fulfills its role by providing various security measures. But the users must take all necessary precautions to protect their data and their funds.
That's true, if the user will not exercise proper care of his account it can easily be hack so that is what you called negligence and if you love money you would always make the right measure to protect your investment, there are ways out there to improve our security so we need to take steps to do that.