User blog comment:IchiNii89/Luffy's Heritage/@comment-108.83.222.210-20190928235942

Those are curious ideas. That being said, while Kuma did send each crewmember to a place where they could train and get stronger, they all had to overcome some obstacle or challenge before they did or at the very least they encountered some form of resistance. Meaning that while Kuma did hope that he would make them stronger, he was very much taking a leap of faith when he did this that the Strawhats would overcome the obstacles in front of them and gain the training that they needed. I suppose in the end he probably chose to assume or believe with good reason that Luffy's crew would manage to overcome these odds. I really wish we could have spoken to Kuma about this before he lost his humanity, it seems he had a great many secrets that should at some point come to light. Just my own opinion on this whole thing, sorry if it is off topic.