Shazam!
I can trace my interest in his show back to my father watching the reruns in the afternoon. I liked what I saw and eventually watched entire episodes. At some point I was able to watch the first season.
I don't know how I got started watching "The Andy Griffith Show" but I'm sure it had something to do with the fact that WFMY Greensboro NC, the market where Mt. Airy, the inspiration for Mayberry, is located, aired the show at 5:30 weekdays for 40 years after first-run episodes ended. It was controversial but they finally joined the 5:00 news trend and eventually that included 5:30 to 6, and I think the show took the place of "The Guiding Light", which meant two a day instead of one.
So I eventually found out he was on that show too, and even dumber, especially in his very first appearance. There's some disagreement over when that was, but I think "Man in a Hurry" may have been the first time people saw him if they were watching the episodes the first time they aired. That was a very detailed introduction to a complete moron who became smarter as time went on. Especially when it came to fixing cars. And giving him his own show just had to happen. He and Sgt. Carter made a great pair.
I also saw his variety show after the show ended. The actors playing Carter and Duke Slater were on that. Duke fell down the stairs every week.