Accounting for your training aids...

The Central Intelligence Agency accidentally left stable “explosive training material” in a school bus last week after concluding a routine training exercise. The Loudoun County, Virginia, school bus unknowingly took elementary and high school students to and from school on Monday and Tuesday with the material under the hood of the bus. The CIA was notified that the explosive training material, insensitive C4, was found in the bus during a maintenance check.

There is always that one time you forget to write down what you have to account for at the end of the day...

http://www.nola.com/politics/index.ssf/2016/04/how_the_cia_managed_to_leave_e.html