That depends on what you mean when you say "system reimaging."
An image is an identical copy of a hard drive. They are commonly used for backup. When you restore an image, the image over-writes the hard drive, so everything that was previously on the drive is permanently gone.
When corporations say they are reimaging a computer, it means they are restoring a previously created image, typically because they are preparing the computer for use by a new employee.
What do you mean by "system reimaging"?