The Spaniard saw his players win the final two fourballs on Saturday to cut the deficit to 10-6 going into the final day, giving them hope and crucial momentum.
Ian Poulter birdied his last five holes as he and Rory McIlroy beat Jason Dufner and Zach Johnson, while Olazabal's compatriot Sergio Garcia and Luke Donald saw off Tiger Woods and Steve Stricker.
And Olazabal said: "The most important part of the week was Saturday afternoon, that session was crucial and I think the players got the feeling of the atmosphere of the Ryder Cup.
"Down the stretch the crowds were very loud but we managed to turn the tide that afternoon session, and I think that was key.
"The way those last two matches went turned around the whole context of the Ryder Cup."
Olazabal hailed the victory as the greatest moment of his career and paid tribute to his close friend Seve Ballesteros, who died last year.
"It's going to take a little while before it completely sinks in," Olazabal told Sky Sports News.
"It's been a very emotional week, especially when things were not going our way, but yesterday everything turned round for us, our players made the putts and had the right breaks at the right times.
"We changed a couple of crucial matches around down the stretch and that gave us the chance to have this trophy back.
"It's completely different from playing, being a Ryder Cup captain. I think in my career it ranks number one."
The 46-year-old lost only two of 15 Ryder Cup games with Ballesteros as his partner and admitted: "Seve's been on my mind the whole week, during the whole journey of this Ryder Cup.
"We had his silhouette and his name on the last day but obviously I had Seve in my mind every day.
"When we managed to retain the trophy, all those memories were very vividly coming to life.
"If someone had written a script for it, that would be the ideal one and for it to happen, Seve had to have something to do with it."
Nicolas Colsaerts, whose debut began with a stunning display as he and Lee Westwood beat Woods and Stricker in Friday's fourballs, likened the trophy to a new arrival in the European family.
"It's safely in our hands and we're glad to take it home," he Sky Sports News. "Everybody at the party wanted to have a bit of a 'conversation with the baby'."
The big-hitting Belgian was unable to add to that first point but admitted he will be desperate for another taste of the addictive cup atmosphere.
He said: "This is by far the experience that has given me the most joy, it was scary... it's a mix of so many different emotions but when it ends like this, it's priceless.
"You don't come across an atmosphere like this anywhere else. It's almost like a fix, you're going to need to play in an atmosphere like this.
"I can imagine how quiet it's going to be for the guys playing in tournaments next week, it's just going to be like you're playing in your garden on your own."