My earliest memory of an interest in fishing was at age 5. I didn't fish then, but saw a bunch of old fishing tackle in the garage, but I don't know that my dad ever used it. In my early teens I happened to see a couple men fly fishing in "my" creek that ran through our rural stump ranch. I don't know if they caught anything, but I thought it was interesting seeing them wading and casting, unlike me sitting on the bank or on a bridge and drowning worms. I subscribed to Outdoor Life and Sports Afield magazines, and hunted and fished vicariously by reading them. I think I was 15 when Outdoor Life had an article titled, "Learn to Fly Cast in 20 Minutes." For unknown reasons my step brother had a glass fly rod in the closet, and I came up with a reel and enameled level fly line. I spent many 20 minute sessions in the back yard with that contraption and still couldn't cast worth a damn. Semi related, I later acquired an 8 1/2' Eagle Claw fly rod and Pflueger Sal-Trout fly reel loaded with 6# mono for fishing Mike's cheese eggs in a couple nearby lakes in the spring. Worked pretty well.
Fast forward a few years to 1971 and while a student at UW in Seattle, the Washington Fly Fishing Club sponsored a fly casting class at Green Lake. Well that's what I had long wanted to do, so I went. Bamboo rod maker Dawn Holbrook instructed the class. I took my Eagle Claw rod and cheap fly reel, and bought a decent Scientific Anglers tapered fly line and by the second class I found my purpose in life. Apparently I was born to fly fish, not spin fish, but I didn't know it because I didn't know how to fly cast. Because I attended that fly casting class I never felt an interest in spin fishing for trout again. A side effect was that fishing with flies was far more productive for me than drowning worms or salmon eggs had ever been, so that likely aided my interest.
Learning to fly cast no doubt ruined an otherwise potentially productive and useful (to society) life. In addition to going fishing more often, because I learned that one could fly fish in WA year around, I devoted practically all my leisure time to reading about fly fishing, learning to tie and then tying flies, building fly rods, bamboo and fiberglass, and then graphite. I discovered that learning about fly fishing was a bottomless pit into which I happily fell. And there I remain. I'm not a fly fishing purist. I had co-workers who encouraged me to return to the dark side of conventional gear fishing for salmon, so I do a little bit of that as well. I've tried to become a more well rounded angler, or Complete Angler in the words of Isaac Walton, but I have yet to fish for capr.