User blog comment:Tayzer/My own league story: supports/@comment-5663427-20131228181445

Well, Taric, Janna, Thresh and rest of pure supports are rarely seen nowdays because Riot simply nerfs them. Compare Thresh's patch notes to Leona's patch notes, while most of Thresh's aspects were nerfed, Leona recieved shorter cooldowns and lower mana costs. And maybe that's the reason why Leona is one of the most popular supports if not the most popular support while the rest are just jokes. Also, unconventional supports are better because Riot gives too much for the "fun" champions, for example: Janna has single target slow, knockback, knockup, shield (crappy after 20 minute)... and that's all, Blitzcrank / Volibear = A lot of tankyness, 100% kill potential, chase abillity, useful in late game. That's another reason why you may see supports more rarely than champions that are not supports, people want to have fun with supports, and that's hard when all you can do is heal your adc for 250 hp ( this equals to 1/3 of usual Adc's crit in late game) or slow ONE enemy champion by 35% for 1.5 seconds.