User blog comment:DancePowderer/Overarching Plot Anyone?/@comment-3213092-20120516210721/@comment-4605926-20120517073759

Oda presented the last line the way it he did in order to create something to wonder about, the end of a chapter has to be ended with some sort of mystery, that's the whole fun in it too.

In that case, he could also tell us so many things that we don't know, like what exactly Devil Fruits are etc.