Either this is the luckiest mouse on the planet or that mousetrap is definitely broken! Either way, this cute little mouse is extremely fortunate to see another day after snacking on a piece of bread. That was tense!
The tinier the mouse, the more likely the trap will not go off. It needs some weight to know when to close. I used to live in an area where we always had field mice come into our home and the same thing happened. BTW...Where did that trap come from? It looks really old.