(Talking about watch movement here, not the brown kind)

I mentioned before that my Prancer keeps stopping when I wear it, and that I thought it's because I keep catching the crown and pulling it out. It turns out I was wrong, it is more interesting than that.

Sometimes the "crown pull" event is triggered when the pushers are operated.

This is a repeatable and demonstrable sequence, so had no choice but to investigate further - so I opened the back



See that black circle around the movement? I don't know it's proper name so I will call it the "spacer ring". Anyway, that spacer is lying on top and can just pop out, like so:



It has been a while, but when I don't remember that happening when I opened my EcoDrive. Could it be that someone replaced the crystal (or serviced the movement) and didn't reassemble in the correct order?

Pictures of the spacer ring for completeness