In addition, if you consider a "Print" dialog, it would be conceivable that it only provides a print preview, but no further inputs, and has only command buttons "Print" and "Cancel". In that case, I still think the menu item should be "Print…" with an ellipsis, despite the lack of further input.

Conversely, you might conceivably have a command that requires additional input, but where the dialog box taking the input doesn't offer the option to cancel the operation. In that case, I would consider an ellipsis misleading, even though a lack of ellipsis might be confusing as well if the command doesn't make sense without additional input.