Naoki Urasawa was not one to back down even if his editors did not support his ideas.
Johan Liebert: The Monster's Life
Every manga's beginning comes with a risk, and Naoki Urasawa's Monster stands as one of the biggest examples. Selling a trope that isn't as common comes with the possibility of it being outright rejected by the editors because of the risks involved. Not only that but where it will be picked up, it is the audience that ultimately determines the success or failure of the projects.
To make a project successful is to crack the formula that makes it so special. For Urasawa, it wasn't just the audience he had to prove a point to, but also the editors. The tropes he proposed were ones they could find no interest in. But with enough thought, it was the formula for success that finally caught on.
During an interview (via Reddit), Naoki Urasawa admitted that making Monster was never an easy task. For a series that later became such a hit, its beginnings were much more rocky than many fans realize. For a series that relied heavily on mystery, for impatient fans, it was a recipe for disaster. His editors understood that and were just as ready to reject the story.
