The Mac Pro Late 2013 has an SSD storage medium which is faster than most medium processor core desktop computers that have been around for a similar time to it. Most desktop computers of this age and type have an HDD storage medium. Solid State Drives (SSD) store information in transistors on a circuit board rather than on optical or magnetic media. This has the advantage of being much faster than a traditional HDD drive.
An SSD storage medium is in fact the best storage speed amongst all medium processor core desktop computers that were launched more than a year ago.
An HDD storage medium is the worst storage speed across comparable types of personal computer.