After the same mistake was repeated over and over, my patience finally ran out.
Usage: Almost exclusively used in the idiom 堪忍袋の緒が切れる (literally, the string of the patience bag snaps). The image is of a drawstring bag that finally bursts open.
Etymology:堪忍 means patience or forbearance, and 袋 means bag. The 緒 is the string or cord that holds the bag shut.