How could everyone, indeed everyone, have failed to notice? The answer is that of course people noticed, but they didn't trust their intuition enough to call Johnsons's bluff. All Johnsons had to do deflect curiosity over the course of the better part of a decade was claim an aunt died and left him an inheritance. Naturally,once the fraud was unmasked, the aunt was discovered to be as imaginary as the stream of phantom shipments Johnsons authorized and his wife paid for.
Clearly, a woeful failure to segregate duties was at the heart of this calamity. Had Johnsons not had the power to approve his own actions, this fraud might have been prevented altogether. Improved transparency and more discipline approval framework would also, at very least, make a fraud such as Johnson's more difficult to launch and impossible to sustain.