1) Karma doesn't have a streamlined gameplay identity that works in unison with her kit.
2) Karma doesn't have a unified kit that works together with a gameplay identity that offers skill expression.
3) Karma doesn't have much skill expression with her basic or Mantra abilities outside of just one use.
4) Karma's passive is extremely powerful and lackluster, but it feels completely useless because it's actually gated by a cooldown.
5) Karma's damage is overloaded in one ability to compensate for the fact that she has no other damage in her kit. This makes her extremely annoying to play against.
6) Karma has utility and sustain on certain abilities that don't belong on it that puts her in roles she shouldn't be in. There is a massive following of players wanting Karma out of top lane.
7) Certain Mantra abilities exist on other champion kits and item actives which begs the question of, what item or champion does Karma's job better?
8) Karma has almost no unique abilities or fun mechanics in her kit that makes a player say, "Hey! I want to play Karma because she is unique!" Players only want to play Karma because she is over-tuned.
9) Karma's thematic is not being properly represented in art or VO.
10) Karma has incomplete art assets that were never completed and it was rushed.
11) Karma has complete skin splash-art but horrible in-game models that are not up to par.
12) And finally, for the past 6 years Riot Game Developers have done nothing on this champion besides back and fourth buffs and nerfs. Riot is doing non-productive work on Karma while saying and acknowledging the type of work she actually needs for 6 years now. In the meantime we have champions like Ryze getting a rework almost every single year, a new champion being prioritized for art and massive kit changes, and three separate Karma communities going at one another because this Development team cannot get their work ethic under control.
We can sit here and go back and fourth with what players want and don't want on Karma. At the end of the day Developers keep saying she needs this and this and this done on her but they keep going back and fourth with buffs and nerfs right after. Riot Game Developers know Karma has art, kit, thematic, and identity problems that they created on her 6 years ago. Where is the same amount of work these Developers keep giving to Ryze every single year and new champions every single year? All this champion has technically received the past 6 years is complete splash-art that doesn't match in game models and a poorly conceptualized running animation that isn't even that great.