I don't get it, Ash has 4 fully evolved starters. Sceptile and Infernape were basically the stars of their respective sagas, winning Ash most of his important battles back then and were powerhouses. Torterra was handled decently until it evolved at least.
And yet, aside from Sceptile having the honor of taking down Darkrai (although it was weakened by Heracross and Gible prior), its not viewed as the same way Charizard is. Despite Infernape going Super Saiyan and destroying Paul, its likely not going to be viewed like Charizard. And then there's Torterra which lost every battle in its final stage aside from TR blast offs.
Why? Why can't the writers ever pass the torch from Charizard to Ash's other heavy hitters?