The problem is ambiguity. Overloading, as we programmers say. Why choose an ambiguous word when a specific one exists? Keep in mind the point of calling it an

The problem is ambiguity. Overloading, as we programmers say. Why choose an ambiguous word when a specific one exists? Keep in mind the point of calling it anything at all is communication, and communication is a lot harder if people don’t hear what you mean. Call it carousel, and someone either gets it, or asks what a carousel is. Call it a slider, and half of your audience assumes you meant something else entirely. (Also, saying a term is not “universal” is pretty much a tautology in the real world, and it is not a valid argument. And a carousel that fades between items is still rotating, just as ads are “in rotation” on the radio even though nothing turns around: yes, rotation is a somewhat ambiguous word, too.)