Problem:The glass on the screen of your Apple Watch is broken or you have damage to your display or touchscreen in any way. The full display needs to be replaced on this device if the screen is damaged.
Lifetime repair warranty on repair (void if physical damage).
Problem:The glass on the screen of your Apple Watch has lifted because the battery has expanded. This is case the screen can be safely removed from the frame without damaging the LCD -- hence you are only paying to replace the battery and not the battery and screen.