I have this recurring debate with other analysts and manager’s: which is better using readiness as an argument, or using mean time between failure? Readiness, is the amount of equipment that is mission capable, divided by the amount you have.

The problem with readiness is that unit commanders can inflate their readiness numbers by flooding the supply system with parts and work their maintenance units like dogs to keep their readiness numbers up. The problem here is you can achieve high readiness by doing this but it hides underlying faults in the equipment.

The issue with using mean time between failure is that most military maintenance management systems don’t capture this well. So how can you tell what you’re mean time between failure is?

One way is to use your readiness number and repair cycle time in a Monte Carlo simulation that can duplicate the fail and repair cycle time of your equipment and estimate your mean time between failure. Can it give you the distribution of the failures? No. But it can help you track what is going on underneath the readiness numbers that really don’t tell you enough.