Why do many computer fraud cases go unreported and unprosecuted?

Many companies believe the adverse publicity would result in copycat fraud and a loss of customer confidence, which could cost more than the fraud itself.

All of these

It is difficult to calculate total losses when information is stolen, websites are defaced, and viruses shut down entire computer systems.

Because of a lack of both funding and skilled staff, law enforcement investigates only a small percentage of computer crimes.