Why was the disposable plastic bottle made? 

How should it fit into the above hierarchy?

It was probably made to hold a liquid of some kind.  If the container was made of recycled, reusable glass instead (with a deposit) the plastic bottle needn't have been made in the first place.

Having been created, filled with the liquid and then emptied, what should happen next? The bottle could be reused again as a container for other liquids (such as drinks).

If this isn't possible, the bottle could be converted to another use, eg as a mini-cloche for a plant, by cutting off the top and standing it upside down over the plant.

The "wasted" top now has to be disposed of.  The plastic section can be recycled and the bottle top can go to a responsibly managed landfill site.