We literally just use people for 1 era, boost them to the top, then trash them and abandon them straight after. We're like the music version of one night stands.
I WILL BE TREMBLING IN FEAR for Jess Glynne.. she is too talented for this! God forbid noooo
Fillers help establish characters and makes you like them. Korras animation change and messy plot was not really good.
S2 was okay but underrated. S4 was pretty bad but had good moments. S1&3 are the best in the franchise tbh. the second half of Aang S2 is the only thing which comes close.