"I wasn’t what you’d call an achiever in school. When I think back, I had a guitar in my hand most of the time." Aerosmith's Joe Perry on The Beatles, Jack White and the ridiculous amount of guitars in his collection

Joe Perry of Aerosmith performs during the opening night of the "Global Warming Tour" at the Target Center on June 16, 2012 in Minneapolis, Minnesota. .

In Malcolm Gladwell’s 2008 book, Outliers: The Story of Success, the British-born journalist contends that “you need to have practiced, to have apprenticed, for 10,000 hours before you get good.”

Let’s break it down, then. That’s a solid 20 hours per week of focused practice for a decade, before Gladwell would even begin to consider you an expert in your field. Here’s someone who certainly cements Gladwell’s theory: Aerosmith’s Joe Perry.