Music mogul Antonio "L.A" Reid will always regret dropping Lady Gaga from his record label, branding it the "worst thing" he has ever done.
"The X Factor" judge signed the star while she was still a struggling singer, but later dismissed her from his roster when he was "having a bad day."
Gaga went on to sign with another label, and Reid admits he made a big mistake letting Gaga go.
He tells Access Hollywood, "This artist came to my office ... she played piano, she had on white go-go boots -- like, all the way up to here, thigh-high boots -- she sat down at that piano, she played and she sang. When she was done, I said, 'You are an amazing artist, a true star, and you will change music,' and I signed her. Her name was Lady Gaga."
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"Then, a few months later," he continues,"I got her demos, and it was a work in progress, and I was having a bad day. I'm telling you, I was having a bad day. And I said, 'You know what? I really don't like it. Let her have her freedom, let her go find her career.' It was the worst thing I've ever done."
However, Reid says he redeemed himself by signing teen sensation Justin Bieber. He says, "I felt bad, but I swear to you, like a month later Justin Bieber came and redeemed me, so, you know, I survived it all. But I'm a little bit jealous, because the Twitter following, for example, the biggest ones are Bieber and Lady Gaga, so I would have felt like the king of the world! Instead I felt like half the king."