McDonald’s recently reintroduced Chicken Tenders, a crispy fried chicken breast treat.

And promptly ran out of them. For an entire month. Because they were too popular.

To make Chicken Tenders one must have chicken breast meat, batter (which is mostly flour, eggs and spices) and a deep fryer. None of these ingredients are in short supply and every McDonald’s restaurant has fryers fired up and ready to go.

For over 50 years McDonald’s has honed its ability to supply its restaurants and deliver hot food fast to millions of people, every day.

It seems unlikely that McDonald’s made a mistake this big. Very unlikely, really.

So what would explain an error of this magnitude?

I think the countdown clock on the McDonald’s website would be a good place to start.