Also the ball will wear and need replacing periodically especially if you run outdoor, worn ball joints will pop cups. Personally I like the Yokomo ball cups over Kyosho cause I can stick my hex driver in to add or remove washers to my camber links for roll center changes without popping them off.
ballcups are designed to pop out after the crash to save other parts of the car. If you break a turnbuckle or something nearby without the cup popping then its not doing its job. As I said on certain high grip carpet tracks, use the white ones but other than that the black ones are fine on clay or dirt.
There's also the option of getting captured links if you never want one to pop.