From the FFXIV launcher:

Currently, we have confirmed that a third party is using account names and passwords, thought to be obtained from security breaches of other companys' online services, in attempts to gain unauthorized access to Square Enix accounts.

If you are using the same account name or password as your Square Enix account on other online services, there is a much greater chance that a security breach at any of the other online services could potentially lead to your Square Enix account being compromised.



Question for the OP: Do you use the same password for your FFXIV account that you use for ANY other service? Any of them? Try to remember please, this could help more people.