It's a phone company. They had an outage. I challenge you to find ONE phone company in the continental US which has never had one.
let's make it even easier: within the last twelve months.
Outages happen. It's unfortunate, but it's electronics. There's a MTTF for every equipment.
With that said, my heart goes out to all those negatively impacted by the events which took place 10 years ago on that fateful day.