Too Late To Save

Or when the Savior arrives too late.

When whatever bad thing that's about to happen to something is guaranteed to happen since no one can possibly prevent it. This is commonly when the heroes can't stop a bad guy (or another bad thing like a large rock or Killer or Global Disease) from killing one of their friends. It can also be Too Late To Save an inanimate object from breaking, stop functioning forever, or being stolen. After it's Too Late To Save, the party whose responsibility was to save the endangered entity will likely be blamed by someone else for their incompetence or latency.