<p>Well, that's not really hard question. First of all everything is subjective and we have right to like and hate whatever we want. But still, BOTH series are epic.
</p><p>So, why do so many people hate LOK? I have my own opinion about that. First of all, as someone already mentioned, it's simply nostalgia. And also people just couldn't accept the fact that Aang, Sokka and other beloved characters are no longer alive and ( as Katara said that ) it's time for new generation to take on the responsibility of keeping peace and balance in the world. People usually can't accept changes.
</p><p>My second explanation is that people just have to be hateful towards something ( it's our nature, what can I say? ). Like shipping wars. It is tv show wars. like wars between Star Trek: TOS and Star Trek: TNG fans, like wars between Game Of Thrones and A Song of Ice and Fire fans, and so on.
</p><p>I grew up watching this ATLA. It was part of my childhood and it really is great and epic show. In all honesty, at the first time, I didn't know how to feel about new series ( and yes, I almost started hating it even before I saw it ). But eventually, it has become my favorite tv show and now I like it even more than ATLA. You can't deny that LOK is for more mature audience and it contains darker and realistic themes. There is violence, poverty, and unkindness as well as nobility, community, etc. Also personally I think that characters are more interesting and have developed a lot. Korra had lot of failures, she was broken, desperate but isn't this more realistic? Aang was brilliant character. He was wise and kind monk, chosen one, call him whatever you want, you can call him messiah if you want. And at the age of 12, he defeated Fire Lord! Yeah, but he hasn't developed as character and person. Aang in a very last episode is the same person he was in a very first episode ( that's my opinion ). But Korra has changed a lot. She started as ambitious, enthusiastic about being "chosen one", teenager girl who faced darkness of real world and politics. Amon took her bending away, Vaatu separated her and Raava and then cut her connection to her past lifetimes permanently, Zaheer tortured, poisoned, crippled her leaving her physically and mentally broken. Then Tenzin and the president were basically saying "you're no longer needed". But she didn't give up and continued fighting. Personally for me she is inspirational. She isn't perfect but her imperfection is what I like about her. Yes, she was 17 ( younger than Aang ) but she lived in different time. Do you think that teenagers of today have same mentality as teenagers in 18th century ( there were rapid changes within 70 years )?
</p><p>And also villains in LOK aren't just "bad guys". They have their motivations, ideology and philosophy. They have actual reasons to leave behind the morals ( not just, I'm the Fire Lord, I want to burn whole Earth Kingdom to the ground! Mahahaha! ). Sometimes you even feel sorry for them. The only villains in ATLA that I was interested in were Sozin and Azula.
</p><p>In conclusion, I would say that ATLA and LOK are both great shows equally. And we can't compare them ( at least IMO ) because they're completely different. You may agree or disagree with me because it's subjective theme ( oh, and sorry for my horrible English ).
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