When the manufacturer changes the item, if the government does not acquire the variant or does not reflect the change in the systems incorporating the item and the systems documentation, the original becomes government unique. After a manufacturer makes a change to an item, the government might be able to purchase and use the new variant without any negative effect to the system. In this case, although the original item is now government unique, the change did not affect the form, fit, interface, or mission characteristics of the device. Unfortunately, manufacturers changes routinely affect form, fit, interface, and mission characteristics, and the effects of these commercial item changes for systems incorporating them are significant. To accommodate form, fit, and interface changes, the acquirer must make modifications to the system.
Modifications are costly and usually result in the original item becoming obsolete.
Changes to mission characteristics do not necessarily result in system modifications, but if they affect the overall ability of the system to perform, they can cause significant problems. For example, if the new software version incorporates undocumented features or unnecessary compatibility, the entire system s security could be at risk. Although software configuration changes can cause havoc in any program, the most devastating cause of government uniqueness occurs when a manufacturer discontinues an item. Figure 2 shows that this is inevitable for a large number of commercial acquisitions. The life of a typical military acquisition exceeds 20 years, yet the life of a typical civil product, especially in electronics is much less.