The singer revealed that she decided to re-release her Teenage Dream album with bonus material to please her "hardcore fans".
Perry told MTV: "With Teenage Dream, the reasons why I wanted to put out this special edition, Complete Confection, is two major reasons for me. One, I'm doing it mostly for the hard-core fans because they always love all the extras.
"The second reason I wanted to do it is because it's my one last push, to push that person that is on the precipice of becoming a fan.
"They're thinking to themselves, 'I bought four or five singles, maybe I should actually complete my album and now I should really complete my album because I'm gonna get 19 songs for a really great price'."
She added: "I think it's like a bargain and I'm doing it for my fans."
Katy Perry's Teenage Dream: The Complete Confection will be released on March 26.
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Listen to Katy Perry's 'Part of Me' below: