so apparently the only reason Xbox is live now is because Kim Dotcom (remember that guy?) "paid" the "hackers" with "thousands of free online storage accounts" to stop attacking Xbox Live... so he could play Destiny.
https://torrentfreak.com/kim-dotcom-...ttacks-141226/
If Kim Dotcom hadn't bargained with them to get Live back online, it would still be off too. It was equally vulnerable to the attack.
The only way to currently defend against random massive DDoS attacks is to acquire bandwidth that is absurdly high, and even then, the "hackers" can just double up their efforts. This is not an example of a company failing to "get their shit backed up."