Taylor Swift opened up to Rolling Stone about her past career mistakes and what motivated several of her musical decisions in the publication's latest issue. One of the most revealing confessions from the interview is what motivated Swift to write her third album, Speak Now, by herself.

Swift describes the several "upheavals" she encountered in her illustrious career, including the role that criticism has played in the making of her music. In one particular incident, Swift was offended that critics of her music said that she didn't write her own songs. She then responded by releasing her album Speak Now, which she wrote entirely by herself.

"I’ve had several upheavals in my career. When I was 18, they were like, 'She doesn’t really write those songs.' So my third album I wrote by myself as a reaction to that," said Swift.

The result produced not only one of Swift's best albums lyrically (the highlight being the brilliantly self-aware "Back to December"), but also one of her most commercially successful releases to date. Speak Now sold more than one million copies in its first week, produced four top 10 hit songs on the Billboard's all-genre chart, as well as seven top 20 hits, and was certified six times platinum by the Recording Industry Association of America.

The album was also lauded by critics, landing on several year-end lists, and was named one of the "50 Best Female Albums of All Time" by Rolling Stone where it was placed at No. 45. Speak Now was also nominated for Album of the Year at the Grammys, Academy of Country Music Awards and Country Music Association Awards. The album's third single, "Mean," gave Swift two more Grammys, one for Best Country Song and the other for Best Country Solo Performance.

Nearly nine years and six million copies sold later, Swift's determination to prove herself created one of the decade's defining country albums.

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