In a conference call with reporters Oct. 30 -- the eve of the reality competition's first live show -- Cowell, 53, opened up about his expectations for the reality star, 28, who debuts with co-host Mario Lopez tonight.
"I think she wants to prove [to] anyone who doubted her that she's capable of doing the job," he said, alluding to some naysayers who have questioned her qualifications (or lack thereof). "I don't know her well, but...she really has got a fun personality. I think she gets what her role is -- she's there to be a voice for the contestants and to have fun with it."
Is he worried about the typically outspoken reality star speaking her mind during the show's live telecasts? Not at all. In fact, he's looking forward to a few surprises. "On live TV, things do go wrong...I kind of like to see the unpredictable, and I quite like to see people under pressure just to see how they deal with it," he explained. "You don't want robots, you want human beings.
"When you want to go off script, go off script," he added. "That's more fun than someone just reading on a teleprompter."
The Brit also said that he has encouraged Kardashian to weigh in on the judging process. "I like that -- [the hosts] are there to have opinions, and I think that's what was lacking last season. It's important that [they] are allowed to pitch in. If they disagree with the judges, they're entitled to say something!"
According to Cowell, Kardashian and Lopez will make a good team in that regard. "They have a good chemistry," he observed. "I think they are going to be fun together."
The notoriously prickly X Factor creator also had weighed in on fellow judge Britney Spears, 30, who was the subject of some scrutiny herself earlier in the season when she was hired alongside Demi Lovato, 20.
"[Britney has] been a lot better than everybody thought," he said, adding that he has been pushing for the "Hold It Against Me" singer to perform on the show. "She's very engaged...She has been, I think, a very, very good judge."
Fans are going to be "blown away with some of the talent this year," the former American Idol judge raved. "It's so much better than what we did last year."