This concept for a watch with a rotating dial was posted by Russian tumblr blogger Hop Picker. It’s design shows how you can safely get rid of extra arrow hands to tell the time.
The simplified watch face is so zoomed in that only the hour hand is needed. Each section of the watch represents a ten minute interval, and the magnified watch face rotates in tandem with a red line.
The concept design is discussed in detail on Reddit. You can see how it would tell the time in the GIF below: