Generally they do not come off, this is the first one I have seen TBH.
You could find it got a knock fro a branch or something.
It is not life threatening so it will not affect anything that will make you crash. But as all things on a bike, it won't hurt to give it a check every now and then.
Before all you airhead riders go looking on your pre LCbikes for this it is only on the LC
