Descriptions of Business Interruption

Data Validation :: Typically, data is not restored until it is required so it is not known if all the data required was actually backed up or if the media on which it was backed up is usable.  Consistent testing of data and services is a time consuming task that is rarely performed.

Momentary Disruptions :: Disaster recovery models do not resolve business interruptions lasting short periods of time such as loss of Internet connectivity, disabled mail servers, etc.

Short term Resumption :: In the event of a disaster, whereby the entire facility is destroyed, the company would need to replace all their hardware eventually in order to return to normal operation.  However, short-term disasters can occur from water damage, quarantines, chemical spills, extended power outages, crime scenes, virus infections, employee error, etc.  In these short-term disasters, it likely would not be necessary to purchase all new equipment for, say, a 4-day outage.  However, the question would remain on how to conduct business during that period.

Environment Replication :: In order to restore complete operations, a company would need to purchase not only new servers but also desktop PCs for all users.  This becomes particularly cost-prohibitive when there is only a brief business interruption.

Hot Site availability :: While purchasing all new hardware after a disaster or business interruption, there is an issue whereby the company would need a place in which to operate.  For example, securing a location sufficient to house all employees and computer systems is cost prohibitive particularly if required immediately.  Such an immediate office-space is required so that the business can continue to operate uninterrupted.