I am not entirely sure why I first played Taric, but the reason I kept playing him was because he made people laugh.
At the time he was commonly considered to be one of the 5 worst champions in the game, up there with Urgot, Galio, and Yorick. However his joke spam combined with his ability to deal a surprising amount of damage and pull clutch 1v2 kills led to vast amounts of hilarity. He was a goofy champion that no one could take seriously, but vs players that didn't know how to fight him (and I met gold+ players that didn't know what his passive was) he was surprisingly strong, especially when ahead due to being a tank who's damage scaled with Armour.
Even when you were crushing lane as him no one could take him seriously and he just made everyone in the game have a good time. I don't think I ever met someone who was salty after being killed by a Taric. I remember Taric as the champion that you could crush a Riven top with and instead of being salty she would just be laughing in /ALL chat. I once dived a full health GP under his turret by myself, then killed both him and their Lee Sin jungler that came to stop me before walking out at half HP. I tanked a good 10 tower shots and it was around the 15 minute mark (Back in early season 5 too) No one complained about Taric being OP because they were too busy laughing about a fed Taric top lane.
Basically I was a Taric main because he made others have a good time just by being in the game.