Books
“I make mistakes like the next man. In fact, being–forgive me–rather cleverer than most men, my mistakes tend to be correspondingly huger.”
— J.K. Rowling · Harry Potter and the Half-Blood Prince

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
A humble-brag with a wink. The speaker admits to making errors like anyone else, then adds that being cleverer than most makes those errors proportionally bigger. It plays on the idea that ability scales the size of mistakes, not just successes.
Context reviewed