Why not? Things break. Electricity is one of those magical things that's very hard to have insanely good uptime -- frankly, it's incredibly impressive that power outages aren't more common.
And in a DDoS, the service typically becomes slower and slower until it reaches the point where only like one in a hundred requests succeeds. With the GitHub outage, it died fairly instantaneously, and it was completely 100% dead. There was no timeout as the servers tried to respond -- the "no servers are available" error page loaded instantly every time.
Considering the attacks within the past year, I was thinking the same thing. I hate to spread conspiracies without foundation, but I wonder if anyone has seen a assessment on the cyberkinetic capabilities of nations around the world?
And why would GitHub not disclose that it was a DDoS? They were very forthcoming when there actually _was_ a Chinese DDoS last April: http://arstechnica.com/security/2015/04/ddos-attacks-that-cr...
And in a DDoS, the service typically becomes slower and slower until it reaches the point where only like one in a hundred requests succeeds. With the GitHub outage, it died fairly instantaneously, and it was completely 100% dead. There was no timeout as the servers tried to respond -- the "no servers are available" error page loaded instantly every time.