What does it mean when i push and hold the voiceover button and it says "all songs,"?

Before reading this take note that voiceover is installed and activated on the iPod that I will be referencing.

So, whenever I hold down the voiceover button (the little button on the top labeled with a little speech bubble) for 2 seconds, the voiceover voice says "all songs,", and finally I get to the question, why does it say that?