Come A Cropper Meaning

(Britain, idiomatic) To suffer some misfortune; to fail.

Example: 1879, Anthony Trollope, The Duke's Children, ch. 67:
  I should feel certain that I should come a cropper, but still I'd try it. As you say, a fellow should try.
1922, Katherine Mansfield, At The Bay, [1]:
  You couldn't help feeling he'd be caught out one day, and then what an almighty cropper he'd come!