WMA has created a system that can track conversions of how many used shipping containers can have an afterlife use for storage. It takes all sorts of different variables and is able to give a good estimate to if the container will be able to be sold after it is used as a shipping container to become a free standing storage container. Many of the variables they use have to do with the amount of time a shipping container had been at sea, the routes the shipping container was used on (Extreme weather conditions can weaken a container making the afterlife a lot shorter), and sometimes even what was in the container. You can check out ShippingContainerForSale.org to see some of the shipping container modifications that have been made.
The aftermarket prices that shipping containers can fetch on the open market is very lucrative, so having this type of information is important to both chipping companies and storage container dealers. Knowing how many trips a specific shipping container can make before it is unusable is extremely important to the aftermarket value. The shipping companies don't want to be left with a bunch of steel containers that cannot be sold afterward. This system is also important for shipping container dealers who buy these containers to sell as storage units. They also want to know the quality of the steel boxes they are purchasing so they can understand the true value before they purchase them. The VMA after life conversion system has fixed a problem for both sides of business.