Cowell admitted yesterday that he made mistakes on the Fox talent show, describing himself as too "cocky" at its launch.
Speaking to reporters, he promised changes for the next season of the competition.
"I can see the second show in my head now, where we need to go with it. We've got a few tricks up our sleeves still," he said.
Despite the criticism of X Factor USA, Cowell offered praise for the first season.
He said: "I think it's been really, really, really good. Compared to the first season we made in England, which was horrific... the first American show was a million times better."
The X Factor's two-night finale airs tonight and tomorrow at 8/7c on Fox.
Watch X Factor finalist Melanie Amaro perform Mariah Carey's 'Hero' on The X Factor below: