The Denny’s restaurant chain is famous for always being open. Established in 1953, the franchise now includes 1,700 locations in 15 countries. Since 1956, the restaurant is known for being open 24 hours a day, seven days a week. Few could have imagined the trouble that would cause on a Christmas 32 years later.

In 1988 corporate management decided to close all restaurants on Christmas. At that time the franchise included 1,221 locations. The decision had consequences, of course. Since the restaurants were always open, closing all of them for one day would result in a loss of $5 million in sales.

There were unforeseen consequences, as well. As a result of the “always open” business plan, many restaurants were built without locks on the front doors. For many that did have locks, it had been so long since anyone used them that no one could find the keys.

In order to comply with the order to close all locations for one day, more than 700 establishments had to install new locks on the doors.

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