"We started terribly and they came at us. We just made too many errors," the three-time Lions tourist told BBC Sport.
"We had a lot of tackles to make and that score line tells its own story. They were clinical at the breakdown and we were terrible."
While the series had already been lost, Ireland were expected to come out fighting after New Zealand snatched a last-minute 22-19 victory in Christchurch last week.
The All Blacks received heavy criticism after that slender victory and O'Driscoll admits Ireland were in for a tough ride following their slow start in the third and final Test.
"We knew that we had to start well and we didn't and that's what the All Blacks do - when they get a 15 or 20-point lead they just play their own game and you're running after them for 80 minutes," added O'Driscoll.
"To be 21 points down before 20 minutes was up, we were going to be chasing the game."
But New Zealand captain Richie McCaw was delighted with the way the All Blacks responded to the earlier criticism.
"It was great, we really picked up in intensity from last week, that probably sums it up even when we didn't have the ball," said McCaw.
"There is always a danger when you get 20 points up that quickly that you might throw the ball around more than you should, but I was happy with the way we got the mix right."