I kind of....didn't, lol.
I really liked and wanted JRTs (and 10 other breeds) from a young age. I like JRTs because of their incredibly intelligence, trainability, and tenacity, but I don't think I was fully aware of the DA/prey drive issues. My parents just bought me a pet store puppy (now I think he's probably a JRT mix). He's had many issues, but I still love the breed.
Pit bulls I just fell in love with working in rescue. And on Chaz, really. Saw some really awesome looking dogs, learned more about them because I became interested in BSL, then we had a lot of great ones in day care, and decided to foster - most dogs at NYC ACC are pits, and I could have requested another breed but I said I was down for whatever.
Breeds that are top list for future are also breeds that I met through daycare and training. My advice to someone who doesn't work professionally with dogs is to go to some dog events, if you have some breeders in mind email local ones and see if you can meet their dogs, dog shows, or go to a shelter and even if you want a breeder dog, you can look around and meet dogs of different types and decide what you're learning towards.