Chris Breaks Down Juan Pablo's 3 Worst Offenses

Chris Harrison dishes on the"worst Bachelor in history."

This season of ABC's The Bachelor featuring Juan Pablo Galavis turned out to be one of the most controversial in the show's history, with some calling the 32-year-old former pro-soccer player the "worst bachelor ever."

Whether it's not proposing to winner Nikki Ferrell, or refusing to even say he loves her on the After the Final Rose special, it's safe to say that some fans were less than pleased with the finale.

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So what were Juan Pablo's worst offenses according to Bachelor host Chris Harrison?

"The first time I noticed he was struggling with embracing the whole concept was in Vietnam with Clare, and the whole ocean thing, and that's when I realized he was kind of serving two masters -- trying to be a dad, and be respectful, yet trying to embrace -- and let go -- and be the bachelor. That's where I noticed he was struggling early-on," he tells ET.

Of course another one of his worst offenses again involves Clare -- particularly a reportedly offensive comment he told her during their helicopter ride together, which Harrison says he still doesn't know to this day.

"I don't know what was said, but [it was] something that really offended her," he said. He had this moment to be sweet, and genuine, and share something off-camera, off-mike, and instead he took that time to say something that apparently really upset her."

Lastly, he counts Monday night's "unsatisfying" After the Final Rose special as the third offense.

"The end goal of our show is to end up with a couple, and I felt like, wow after all of this, we did it -- we have a couple who loves each other -- but he just wouldn't give, and he just won't, and I don't know why," a clearly frustrated Harrison says. "I don't know where all the anger, and all the angst, or reservations come from, I don't know ... throughout it, I feel like he was his own worst enemy."

Harrison also dishes that Juan Pablo was very "controlling" throughout the whole experience, even early-on.

"He really tried to control the situation, and it's a situation that you can not control," he says. "To have it work, you really have to give up yourself to this thing. ... He couldn't get there. And from the beginning, he tried to sneak his first kiss with Clare off-camera -- he did sneak his first kiss with Nikki off-camera. He would try to say things and do things off-camera, and it was like, 'Well if you're that worried about it, why are you doing this?' And this is early-on -- we're talking week one."

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Check out the video to hear if Harrison "dislikes" Juan Pablo, and if he feels his relationship with Nikki will last.