Best laid plans of mice and men

The phrase "the best laid plans of mice and men often go awry" or simply "best laid plans" is a simple proverb meaning that even carefully planned projects may sometimes still go wrong.

The saying is an adaptation from a 1785 poem by Robert Burns titled "To a Mouse, on Turning Her Up in Her Nest with the Plough." The line as originally written goes "The best-laid schemes o' mice an' men Gang aft agley." It was also used by John Steinbeck for the title of his 1937 novel "Of Mice and Men."