I also think the job is really taxing physically and mentally. So sometimes they just let it go.
they also have pressure from every direction : the editors, the studio, the fans (local and international) etc etc. All wanting différents things.
And I think writing something for years and years with all those constraints, new directions, and the characters created having sometimes a better impact that you thought (or worse).
I dont think as a young mangaka creating your universe you can master all those parameters
Definitely true.
Which is why I mentioned the cookie cutter ending part.
All these shonen are going to end in some feel good way, where the protagonists win somehow, there are a couple of chars dying, one that's noteworthy, but nothing major.
Even when the ending has a twist, like say Shaman King and Hao, the main villain, winning and becoming the Shaman King, they soften him up etc.
So yeah.
But sometimes you gotta write it differently imo. AOT, for instance, would probably have been the GOAT, or at least in the top 5, if the ending was done the way it should have been done.