Was it a loose pin or something? I mean, I had one where the shoe was cracked right at the hinge but it just looked dirty, idk. The whole thing slipped off the second we tapped it and scared me straight. I check that hinge spot like three times now, no joke.
Probably the same thing everyone misses, the obvious stuff. It's always hiding in plain sight, like my keys when I'm late. Bet it was right in front of you the whole time.