There is no such thing as perfect account security. The other end of the unpredictable coin, is you, the end user. Do not share your accounts or passwords. Use complex password that are not in the dictionary. Use long password. Keep you PC clean by running antivirirus software. If you don't know what you're installing then don't install it. Do not open email form people or place you do not know.

I could go on and on. if there was a breach on SEs end, then certain steps could be taken to protect your data. However, it's up to you to protect your PC.