Nova: "saving" and "saved" not fired?

Hi guys! I´ve a component that creates a slug when a model is saved. For that it uses the "saving" (or "saved") lifecycle event of the model. Works great so far.

However, when I create a new Model instance via Nova UI ("Create"), then it looks like these events are not fired. Do you have an idea, what´s going on here and why these events are not fired?

Thank you in advance, beste, Michael