The UEFA president told sports newspaper L'Equipe that he doesn't regret his own vote for Qatar and still thinks the Gulf nation "was the right choice for FIFA and for world football."
"But if instances of corruption are proved, there will need to be a new vote and sanctions," Platini said.
A FIFA prosecutor plans by next week to wrap up his investigation of the 2010 votes for Qatar and 2018 World Cup host Russia.
On a personal note, Platini claimed that "somebody, something" is plotting to discredit his possible candidacy for the FIFA presidency.
Media reports this week cast doubts on Platini's links to now disgraced Qatari official Mohamed bin Hammam. London's Daily Telegraph alleged Platini had "a secret meeting" before the 2010 vote with Bin Hammam, suspected of vote-buying and other irregularities and whom FIFA subsequently expelled in 2012.
Platini told L'Equipe it was simply breakfast with a work colleague. Bin Hammam, like Platini, was a member of the FIFA board.
"I read 'Platini corrupt?' in all the newspapers, on news agency wires, on blogs. Honestly, it hurts," Platini said.
He added: "I saw this colleague 10,000 times in 15 years. Why would I have had a secret meeting with him? I now realize that in the background there is somebody, something, people organizing all this. I can feel it."
"For a year now, everything is being done to discredit me, regardless of what I do. It is easy to feed people who spend their time denigrating you on social networks. There are firms that specialize in this. It's not hard, you simply have to pay."
Platini stopped short of accusing FIFA and its president Sepp Blatter of involvement.
"I have no proof," he said. "I don't know who is behind all this. But I think lots of interests are at stake, for those at FIFA, for those who want to be there" and "without doubt also for those who want us to overturn the attribution of the 2022 World Cup to Qatar."
Platini said, however, that none of this will influence his decision on whether to challenge Blatter for the FIFA presidency. Platini said he will announce in August, after the World Cup in Brazil, whether he will run in the May 2015 election.
Blatter is looking to next week's FIFA congress to support his own ambitions for another four-year term.