straw that broke the camel's back

The phrase "straw that broke the camel's back" is an idiomatic expression that refers to a seemingly small or insignificant event or action that causes a sudden or unexpected collapse or failure. It represents the final and decisive action that causes an overloaded or burdened system to collapse or a person to reach their limit or breaking point. The phrase is often used to describe a situation where multiple factors or burdens have been accumulating, and the addition of one more relatively minor factor becomes the final catalyst for a notable and often dramatic outcome.