The Pavilion x360 has an HDD storage medium which is better than the SSD storage medium found on most 2 in 1 laptops that have been around for a comparable time to it. HDD is a traditional storage drive which stores the information on magnetic disks. HDD drives are slower than other forms of storage such as solid state drives (SSD) and flash drives.
This portable PC's storage medium (HDD) is in fact the worst storage medium across all comparable spec notebook PCs that were released around the same time as the Pavilion x360.
The best storage medium across similar types of portable PC is SSD.