Why are these webtoons low-rated?

There is nothing more useless than the rating system of Webtoon. It is because almost everything has 9 stars and above.

However, recently I have seen some Webtoons that have been massively disqualified. This has happened to those Webtoons that revolved around dark/heavy/controversial topics (Like "Cry or Better Yet, Beg") or because they had dark/heavy/controversial episodes (like "The King and the Paladin" and "Who Stole the Empress") I don't have to go into details because they have been ranted on Reddit so much.

But, in the case of these specific Webtoons on the pictures, why are they so low-rated? It is because they talk about dark/heavy/controversial topics? Or it is because they are bad? Are they plain, boring or something else? Have they suffered from bad-written or badly executed plots?

I haven't seen posts about these webtoons on the pictures (maybe because they aren't popular) that's why I'm genuinely asking for your opinion.