There are people out there that simply like to bring frustration to others and when those people learn how to preform DDoS attacks (distributed denial-of-service attacks*) the level of frustration is just too damn high.
Last week during the launch of World of Warcraft: Warlords of Draenor, Blizzard was hit with DDoS attacks – this week it's Square Enix's Final Fantasy: A Realm Reborn NA/EU game servers.
The DDoS attack does not put character data or personal information of the players at rise, but it does mean that there will be server and log in difficulties – so, if you're disconnected from the game don't be surprised. Square Enix's technical team is working on a way to mitigate the attack or to address the entire issue itself.
Blizzard handed out extra game time for their launch issues and while FFXIV: A Realm Reborn is an established game, perhaps we will see free game time from them as well (hopeful thinking).
*An attack attempting to increase the server load to an extensive level by flooding the network of the targeted servers using a massive number of computers.