A lot of pets will ignore you, but only a cat will follow you from room to room and check your lines of vision to make absolutely certain that you can see them ignoring you.
A lot of people are interpreting this as a “cats don’t really love you!” screed, or a misunderstanding of how cats interact socially, but what I’m really talking about is how if you do something to annoy or upset a cat they’ll “punish” you by very pointedly withdrawing attention, turning their back and refusing to interact, yet if you go to a different room they’ll follow you so they can ignore you there.