Is headset dust cap suppose to rotate?

*Pic for illustration only (not my bike)*

Image: https://farm5.staticflickr.com/4392/36921160272_d964864911_z.jpg

So I took the opportunity to give the headset bearings a wipe and re-grease. I put everything back the way it supposed to and tighten the top cap about 3nm (I'm always worried...