I have to say, Patton's quote is something I've often explained to younger people in my business, as I am trying them. Part of the event process, is rehearsing things. Part of the rehearsals is making sure you have plans, and backups. Live events means things can and will go wrong, and off script fast.

Learning to plan, and make backups is HUGE.
And learning to see, analyze input quickly, and make changes on the fly is also important. Planning for contingencies and backups is all part of a successful campaign.