I noticed that first mecanim clip rotates the cube but only once, while however the second mecanim loops itself going up then shoots back down to bottom and goes up again.
You can have it setup to loop animation states or play them once. It's a combination of the transition used, the animation clip itself and what type of logic is implemented. In this lesson I used an int and bool parameter which stays in that state unless I change it through inputs. So animations could stay looping in one state until I change the parameter value.
I could also have it setup to automatically transition on it's own when the animation has finished playing. The rotating cube animation more than likely is setup to loop from what I remember. You can click on the animation clips in the project panel and you'll see an option to loop them in the inspector. If that is checked the animation can loop, otherwise it'll play once.