When all ocean-going ships depended upon the wind to blow them along, a wind
favourable to a vessel travelling east was unfavourable to one travelling
west; but as ships were voyaging all over the globe – one westward, another to
north or south – there was seldom a wind ‘blew nobody any good’, that did not
benefit anyone at all.

By extension this proverb means that every calamity, loss or misfortune is of
advantage to somebody. If Mr Harrison’s house is struck by lightning, Mr
Johnson makes money out of repairing it; and if Mr Wilkins misses the last
train home, the taxi-driver profits in consequence