When everything that can go wrong, does. This is a popular
concept in
computer science, especially with
algorithms. For example: If you create a
binary search tree by
iterating through a
sorted list, you'll get a "tree" with no branches, which is
worse than useless. See
run-length encoding for another example.
Bubble sort is an
interesting algorithm because the
best case is just as bad as the
worst case, and so are all the other cases in between.
Bubble sort is taught to
CS freshmen because it's not only
inefficient nearly to the point of uselessness, but also relatively
unfathomable in comparison to other more
efficient sorts. It's still better than
bogo-sort, if you're into
faint praise.