Big Boss is spot on...if it's on tight/correct and fits correctly, it shouldn't come loose.
Just compared the two pics, as Buzz did...good eyes mi amigo.
Murph...turn the damn spinner slowly against the pin to duplicate what Buzz is describing you should see contact against the top of the pin. Might take harder force (hammer or centrifugal) to make it happen, but there is definitly a difference in the ears.