Don Knotts wanted to be an actor first, and then comedy followed
He loved movies first, and comedy second.
Being a comedy performer is one of the hardest jobs in Hollywood. There are so many factors that make it complicated. First, it's not enough to be funny. Anybody can stand in a break room and tell a joke, but not everybody can lead a scene in a sitcom. The difference is a compelling performance. Many standup comedians discover that they don't have what it takes to carry a movie or even an episode of a show. Comedy actors need to be actors first and foremost, and then they need to have that intangible funniness sprinkled on top. You can learn how to be an actor. You can not learn how to be a comedy performer. It relies on things like instincts that can't be taught.
Don Knotts is the perfect example of a performer who can do it all. That's critical to what made him so watchable on The Andy Griffith Show. He was so funny. But, crucially, he wasn't just Mayberry's clown. Barney Fife had a full spectrum of human emotions, requiring Knotts to act his heart out. Don Knotts convincingly conveyed whatever feeling the script called for, and he did it over and over again. Yes, Barney is frequently the butt of the joke. But he's also a whole person. Any other actor may have only been able to persuade us of the former.
It's no coincidence that Knotts first wanted to be an actor when he was a little kid. In an interview with Disney Channel Magazine from back in January of 1986, Knotts explained how fundamental the silver screen was to his development as a youngster.
"I spent the first seven years of my life in the dark, looking at those moving shadows on the silver screen," he said.
"By the time I was eight, I knew I wanted to be an actor. A comedian I didn't know about yet, but an actor I did."
Shortly after he found his love for cinema, the young Don Knotts discovered that he was a fan of radio comedies. He's since cited Edgar Bergen, Joe Penner, Jack Benny, and Fred Allen as his favorites.
"Thanks to radio," said Knotts, "I knew something about timing before I was out of grade school."
He later pursued comedy, but always kept himself rooted in performance. There's no arguing about it; Barney Fife would've been very different if Don Knotts hadn't first found a love for acting. Any other actor would've risked Mayberry's Deputy becoming a caricature.