No idea. Some sort of program that adds automatically adjectives to your descriptions and slightly modifies passages you have already used. So you can recycle scenes over and over again with little variation. Same situation, just different setting and names against your new bully type enemy.
And it obviously helps that the overall plots and arcs of most Chinese novels is rather similar. So you can copypaste well without being caught. Childhood arc, special spiritual sensei arc, imperial academy/sect entrance arc, cultivation arc, some sort of academy tournament arc, etc., etc.
It's because they get paid for producing a certain amount of words per month/week, otherwise they don't get any money for their novel anymore.
The longer their novel lasts, the longer they'll get money.
Thus, you end up with recycled arcs and plotlines with little to no character development to ensure maximum chapters.
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