Oops was a German naval term

Rico says it's sometimes the simplest thing (like not throwing the code books overboard) that changes history:

Philip Wilson, trustee and archivist of the Warwickshire Yeomanry Museum and member of the Royal British Legion:

Hew Cleland Hoy, in his book How The War Was Won, published in 1932, says that enemy code books from sunken German ships found their way to 40 OB early in the War and these, which were luckily succeeded by similar captures in the course of time, proved of considerable assistance to the deciphering department. Suspecting this form of leakage, Germany tried to cover it up and, in 1916, altered the key of their principal Naval Signal Book. But as they, ignorant of our interception of their wireless, broadcast this to the High Seas Fleet one night at midnight, 40 OB was, within hours, once more in possession of the solution of the enemy’s naval communications.’
Sir Basil Thomson, in his introduction to this book, says Hoy was a private secretary to the Director of Naval Intelligence, Admiral Hall, whose handling of the Zimmerman-Carranza telegram (promising the states of New Mexico, Texas, and Arizona to Mexico, if she would declare war on the United States) that did more towards bringing America into the war than the sinking of the Lusitania had done, for if he had used the ordinary diplomatic channels it might never have reached President Wilson. In writing this book, Hoy makes it clear he was bound by the Official Secrets Act and, in making his compilation, says: ‘I have had to remember, and also to forget.’