When a new Image/Object is added to the Objects and Animation Editor, it just has one Key Frame located at the start of the Timeline.
Example: To Pan an Image from Left to right we can Clone a KF and drag the Image from its start position to its end position. We might want to adjust the Saturation in the middle of the Pan. By adding a Blank KF we can turn on the Colour Correction Filter and make the necessary adjustment without influencing the nature of the Pan.