[jmull]

Well...

You've made a couple mistakes here.

1. You've made the unfounded leap that the diagram intends to represent state after the button has fired. That's manifestly incorrect.

2. You've made the incorrect assumption that a full reset of the diagram is accomplished by clicking the button. But that's not what it says. Obviously, you also need to move the mouse out of the button to return to the start state. So you could criticized this for incomplete instruction, however, since the context is a demo for a college course, omitting over-instruction of obvious and irrelevant details is most likely the best decision to reach the overall instructional goal.

If you want to be pedantic on the internet, you need to go a bit deeper than that. ;-)