Toki is a tribute to time and its perception. Time, symbolized by the rotating top, is seemingly moving forward in a linear manner. Our perception, however, may fool us. When having a good time, it seems to pass quickly while in a less enjoyable context, a minute can feel like an hour.
The contradiction between the time physically passing and our perception is symbolized by the ball on top of Toki. It tries to match the movement of its underlying disk, but always struggles a little while being pulled back.
Over the years Toki is self-engraving that contradiction and showing the passage of time figuratively and literally.