Changing backgrounds are for people, not cats.

Cats and Humans "see" things differently as far as entertainment goes.
Humans prefer motion, plots and realistic scenes. Humans get bored quickly
if the subject never leaves their location. An example would be a movie about firefighters, and they never leave their room. How boring.

Cats, on the other hand.. are hunters. In fact, cats are one of the most
efficient and successful hunters on land. One reason is because they "fixate" on their prey. Cats do not understand plots, nor do they have scene changes
as they hunt. Cats see something of interest move, and will plot and
study every possible plan of attack. That is what excites a cat.

Changing backgrounds may actually distract cats, briefly making them
loose their "plan". This can frustrate a cat, just like it would for humans when
we are interrupted a lot when trying to focus on something important.
Remember.. to your cat, this is real, not TV.