Platini backed Ukraine and Poland's bid when they were chosen in April 2007 to co-host the event shortly after he became UEFA president.
But the build-up to the tournament was a troubled one, blighted by spiraling costs, delays in both countries and political instability in Ukraine.
He threatened several times to move the event from Ukraine, and opened up about his personal feelings at a news conference on Saturday, one day before Spain met Italy in the final at Kiev's Olympic Stadium.
"I was very tense, very stressed out, before this tournament. I came in very tired because I had a lot of pressure on my shoulders for the last four or five years to see if it would work," he said.
"Today I'm more relaxed, calmer. We had criticism before the tournament and we needed to respond to it. That's why I was tired but now I'm less tense and can't wait for my holidays next week."
Despite his initial fears and widespread scepticism that the two Eastern European countries could stage the event, he endorsed their efforts on Saturday, praising everyone involved in its success.
"Poland and Ukraine have organised a fantastic tournament which has been unique in its atmosphere.
"More than 1.3 million people have gone to matches in the stadiums, which is a record, and the Euros will leave a very important legacy in these countries.
"Never before has a slogan been more true - 'lets create history together' - in terms of the economy, the infrastructure, in terms of football development, in terms of social development, and promoting these countries all over the world."
He said that TV viewing figures around the world, not just in Europe, had never been higher, adding, "we've seen higher market shares even in countries that haven't played here.
"Two-thirds of the people have watched it even when their teams were not taking part.
"But in Germany, games from Euro 2012 had 122 percent higher viewers than the Champions League final. A match involving Italy was 60 percent more higher than viewers for the [2010] Champions League final involving Inter Milan and Bayern Munich.
"In Britain, 66 percent more people watched than when Manchester United played Barcelona in the Champions League."
Figures in Asia and the United States were also improved he said.
"It's not just a European tournament any more. We had greater viewer figures in the United States and Asia, almost double the audience of Euro 2008."
GREAT FOOTBALL
Platini also praised the football on the pitch as the well as everything else off it.
"Euro 2012 has really showed how much quality, intensity, and technical ability there is in European football. There's been fair play, the referees have been fair, balanced and very good."
And he could not resist praising UEFA's implementation of their five-man refereeing teams, which he said was far better than goalline technology, of which he rema
