The last summer of Klingzor

Three nales of Herman Hesse - “The Soul of the Child”, “Klein and Wagner”, “Last Summer of Klungzor” - were first published, at the insistence of the author, by a single collection during his lifetime, and since then they are invariably published together.
But Why did the writer consider the works so different, at first glance, works? What is in common about the stories about a little boy, tormented by the torment of conscience because of a handful of stolen sweets, a small servant who fled abroad with a money stolen from a company, and a dying great artist who spends the last summer in his life?
The secret of this unobvious internal connection is actually simple: the heroes of all three novels of Hesse are people who experience a radical breakdown and revaluation of their own values